4,792 results on '"COLLOIDAL stability"'
Search Results
2. Influence of nanofiller surface treatment on mechanical properties of pyrolyzed ceramic nanocomposites.
- Author
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Viswanadha, Laxmi Sai, Wu, Chenglin, Watts, Jeremy, and Naraghi, Mohammad
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SURFACE preparation , *MATERIAL plasticity , *COLLOIDAL stability , *FRACTURE toughness , *ZETA potential - Abstract
The brittleness and limited plastic deformation of ceramics restrict their applications. In this work, the effects of pristine (CNT P), functionalized (CNT OH , CNT COOH) and silanized MWCNTs on the mechanical properties of Silicon Carbide obtained by pyrolyzing polycarbosilane SMP-10 were studied. Functionalization with 3-glycidoxypropyltrimethoxy was analyzed through dispersion stability, zeta potential, and EDS analyses, revealing increased silicon content and colloidal stability in silanized MWCNTs. However, silanized MWCNTs led to reduced mechanical properties in composites, while untreated MWCNTs (CNT P , CNT OH , CNT COOH), showed a substantial increase in modulus by 74.2 %, 86.9 %, and 30.5 %, respectively. The observed enhancement in mechanical properties exceeded the outcomes predicted by the rule of mixtures, suggesting notable morphological changes induced by MWCNTs. Potential underlying factors including toughening mechanisms and changes in porosity were evaluated and discussed in depth. Composites with untreated MWCNTs showed nearly a two-fold increase in fracture toughness. This work shows a streamlined approach for the development of ceramic nanocomposites (CNCs), achieving significant improvement in mechanical properties through pyrolysis, surpassing traditional methods reliant on densification processes. These findings demonstrate the substantial potential of CNCs, enhancing their suitability for advanced engineering applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. Strategies to Protect and Deliver Curcumin via Zein Nanocomposites for Food Applications.
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Hassane Hamadou, Alkassoumi, Zhang, Jiyao, and Xu, Bin
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INTESTINAL barrier function , *HYDROGEN bonding interactions , *COLLOIDAL stability , *BIOACTIVE compounds , *CURCUMIN - Abstract
Curcumin (Cur) considered as a golden nutraceutical, is emerging as one of bioactive compounds demonstrating the most promising biological activities, including antioxidant, antibacterial, anti-inflammatory, anticancer. It is also used for coloring and seasoning in foods. However, Cur applications are limited due to factors like low aqueous solubility, poor colloidal stability and bioavailability. Extensive efforts were made using pure zein (Ze) to develop nanoparticles (NPs) for encapsulation of Cur to overcome the aforementioned issues. Nevertheless, zein nanoparticles (ZeNPs) have limitations related to their instability to neutral pH and rapid degradation by gastric proteases. Thus, the combination between Ze and different biopolymers to produce zein nanocomposites (ZeNCs) for improving the stability of ZeNPs were scrutinized in this study. The mass ratio of Ze/polymer played a critical in the formation and stability of ZeNCs. Electrostatic attraction, hydrogen bonding and intermolecular interaction were responsible for ZeNCs formation. High encapsulation efficiency (EE), storage stability, solubility, bioaccessibility, intestinal permeability and antioxidant activity (AA) for Cur were achieved in ZeNCs compared to ZeNPs. ZeNCs did not show toxicity towards normal NCM460 and 293 cells, but potent anticancer activity against MCF-7, HepG2, Hela, and HCT 116 cells. ZeNCs displayed potential applications in different food matrices. [ABSTRACT FROM AUTHOR]
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- 2024
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4. A solvothermal method for the synthesis of dual paramagnetic and upconverting luminescent β-NaYF4:Yb3+,Ln3+@NaGdF4 (Ln3+=Er3+ or Tm3+) core@shell nanoparticles.
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Molina-González, Jorge, Rivera, Aura A., and Ramírez-García, Gonzalo
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MAGNETIC nanoparticles , *COLLOIDAL stability , *CONTRAST media , *HYSTERESIS loop , *CHEMICAL yield - Abstract
The interest in the applications of upconverting luminescent nanomaterials has expanded significantly, particularly in the biomedical field. An opportunity for innovation in this realm lies in the development of multimodal contrast agents that exhibit both luminescent and magnetic responses. This study presents an easily reproducible strategy for the solvothermal synthesis of NaYF 4 :Yb3+,Ln3+@NaGdF 4 (Ln = Er3+ or Tm3+) core@shell nanoparticles. The shell incorporation process initially involved dissolving the outer layer of NaYF 4 :Yb3+,Ln3+ cores, followed by the radial growth of NaGdF 4 around them. This shell provides intense paramagnetic properties without affecting the luminescent response of the cores. The optimized process yielded individual core@shell nanoparticles, with average diameters of 20 ± 5 nm for NaYF 4 :Yb3+,Er3+@NaGdF 4 and 19 ± 3 nm for NaYF 4 :Yb3+,Tm3+@NaGdF 4 UCNPs. The presence of NaGdF 4 shells was further confirmed by Raman spectroscopy, which revealed a change in polarizability within the structure due to the presence of Gd3+ instead of Y3+. Based on the hysteresis loops, the magnetic response of NaYF 4 :Yb3+,Ln3+ was negligible, whereas NaYF 4 :Yb3+,Ln3+@NaGdF 4 exhibited saturation at 1.04 emu/g at 20 kOe. Compared to common thermal decomposition approaches, this method offers several advantages: it provides nanoparticles that are colloidally stable in aqueous solutions, a higher reaction yield, eliminates the need for an inert atmosphere, reduces the excessive use of solvents for separation and washing, and requires less experimental manipulation. Therefore, this method enables the synthesis of materials with applications in the development of sensors, contrast agents, or theranostic tools with dual magnetic-luminescent responses. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Producing high‐colloidal‐stability sesame paste: structural role of stone milling‐modified protein.
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Yang, Dongmei, Du, Chenxing, Tang, Zijian, Duan, Zhangqun, Luo, Shuizhong, and Zheng, Zhi
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CYTOSKELETAL proteins , *HYDROPHOBIC interactions , *COLLOIDAL stability , *LASER microscopy , *CUSTOMER experience - Abstract
BACKGROUND RESULTS CONCLUSION Sesame paste faces issues with poor colloidal stability during storage, thereby affecting product quality and consumer experience. This study aimed to modify the proteins in sesame paste through stone milling and investigated the differences in stability produced in this environment, with the goal of addressing this issue.As the number of grinding times increased from one to three, the median diameter of sesame paste significantly decreased from 85 to 74 μm (P < 0.05), and the centrifugal oil separation rate dropped from 9.05% to 6.82%. Rheological measurements indicated an increase in the flow behavior index (n) from 0.51 to 0.61. Confocal laser scanning microscopy results revealed a more uniform co‐distribution of protein and oil when ground thrice. The β‐sheet content of the protein in sesame paste increased from 52.92% to 56.34%, with enhancements in surface hydrophobicity, hydrophobic interactions and emulsification of protein. When the number of grinding times increased to five, the particle size of the sesame paste was further reduced and the β‐sheet content of the protein decreased to 51.00%, while the oil separation rate increased to 7.78%.Stone milling induces structural modifications in proteins, which in turn alter the internal structure of sesame paste, resulting in varying levels of oil separation at different grinding times. Among them, sesame paste ground thrice showed a 25% reduction in the oil separation rate and experienced minimal oil separation over 120 days, making it suitable for practical production. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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6. Liquid-encapsulated quantum dot for enhanced UV and thermal stability of quantum dot color conversion films.
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Liu, Ronghuan, Fang, Fan, Liu, Pai, Duan, Xijian, Wang, Kai, and Sun, Xiao Wei
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SEMICONDUCTOR nanocrystals ,QUANTUM liquids ,ULTRAVIOLET radiation ,COLLOIDAL stability ,THERMAL stability ,QUANTUM dots - Abstract
Encapsulation is a widely recognized method for enhancing the stability of colloidal quantum dots (CQDs). However, traditional encapsulation methods for solid-state materials expose encapsulated CQDs to risks such as ligand loss and poor dispersion. Additionally, these encapsulated CQDs still face the risk of aging due to surface ligand bond breakage under high-energy radiation. In this study, we found that quantum dots in solution exhibited enhanced ultraviolet (UV) tolerance compared to their counterparts in solid form under an inert atmosphere. We attribute this enhancement to improved ligand retention and self-healing of quantum dots in solution. Herein, we introduce a novel method for fabricating liquid-encapsulated quantum dot (LEQD) color conversion films. This technique leverages the self-healing capability of ligands in liquid-state quantum dots to enhance the UV and thermal stability of the quantum dot color conversion films. Experimental results demonstrate that LEQD films exhibit better resistance to UV radiation and high temperatures than solid-encapsulated quantum dot (SEQD) color conversion films. After 400 h of exposure to 100 mW blue light-emitting device (LED) light at 60 °C and 90% humidity, the brightness of LEQD film retained 90% of its initial level. This liquid-state quantum dot encapsulation approach offers a promising pathway for developing more durable quantum dot color conversion films. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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7. Charge-assisted stabilization of lipid nanoparticles enables inhaled mRNA delivery for mucosal vaccination.
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Liu, Shuai, Wen, Yixing, Shan, Xinzhu, Ma, Xinghuan, Yang, Chen, Cheng, Xingdi, Zhao, Yuanyuan, Li, Jingjiao, Mi, Shiwei, Huo, Haonan, Li, Wei, Jiang, Ziqiong, Li, Yijia, Lin, Jiaqi, Miao, Lei, and Lu, Xueguang
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SARS-CoV-2 Omicron variant ,COVID-19 vaccines ,CANCER vaccines ,SURFACE charges ,COLLOIDAL stability - Abstract
Inhaled delivery of messenger RNA (mRNA) using lipid nanoparticle (LNP) holds immense promise for treating pulmonary diseases or serving as a mucosal vaccine. However, the unsatisfactory delivery efficacy caused by the disintegration and aggregation of LNP during nebulization represents a major obstacle. To address this, we develop a charge-assisted stabilization (CAS) strategy aimed at inducing electrostatic repulsions among LNPs to enhance their colloidal stability. By optimizing the surface charges using a peptide-lipid conjugate, the leading CAS-LNP demonstrates exceptional stability during nebulization, resulting in efficient pulmonary mRNA delivery in mouse, dog, and pig. Inhaled CAS-LNP primarily transfect dendritic cells, triggering robust mucosal and systemic immune responses. We demonstrate the efficacy of inhaled CAS-LNP as a vaccine for SARS-CoV-2 Omicron variant and as a cancer vaccine to inhibit lung metastasis. Our findings illustrate the design principles of nebulized LNPs, paving the way of developing inhaled mRNA vaccines and therapeutics. The instability of lipid nanoparticles during nebulization hinders inhaled mRNA vaccines. Here, the authors report on a charge-assisted stabilization strategy using a peptide-lipid conjugate to improve lipid nanoparticle stability, enabling mRNA-based mucosal vaccines for SARS-CoV-2 and lung cancer. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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8. Recent advances in surface decoration of nanoparticles in drug delivery.
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Phuong-Dung Ly, Ky-Nhu Ly, Hoang-Long Phan, Nguyen, Huong H. T., Van-An Duong, and Nguyen, Hien V.
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TARGETED drug delivery ,SURFACE stability ,DRUG target ,COLLOIDAL stability ,NANOPARTICLES - Abstract
Nanoparticulate delivery systems have been attracting attention in pharmaceutical sciences for enhanced drug bioavailability and targeted delivery. Specifically, these systems can enhance the solubility of poorly water-soluble drugs, protect therapeutic agents from degradation, prolong circulation time in the body, control drug release, and facilitate the precise targeting of drugs to specific tissues or cells. However, once administered into the body, nanoparticles often encounter significant challenges that can affect their efficacy and safety, such as issues with stability, biocompatibility, and targeting. The surface properties of nanoparticles are one of the most important features as they can greatly influence the interactions between nanoparticles themselves and between nanoparticles and biological targets. Key surface characteristics, such as charge, hydrophobicity, and the presence of functional groups, determine how nanoparticles behave in biological environments, thereby influencing their stability, cellular uptake, and ability to avoid immune clearance. Modification of the nanoparticle surface has been shown to be an effective approach to modulate the physicochemical and biological properties of nanoparticles, achieving desired therapeutic efficacy in vivo. This review aims to summarize recent advances in surface decoration of nanoparticles, with an emphasis on improved colloidal and biological stability, reduced toxicity, and enhanced drug targeting. The challenges and future perspectives of nanoparticle surface modification approaches are also discussed. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Polymeric nanoparticles loaded with vincristine and carbon dots for hepatocellular carcinoma therapy and imaging.
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Fawaz, Walaa, Hanano, Abdulsamie, Murad, Hossam, Yousfan, Amal, Alghoraibi, Ibrahim, and Hasian, Jameela
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BIODEGRADABLE nanoparticles , *LIVER cancer , *COLLOIDAL stability , *HEPATOCELLULAR carcinoma , *CELL survival , *POLYCAPROLACTONE - Abstract
Chemotherapy for hepatoblastoma is limited by organ toxicity and poor outcomes, prompting the search for new, more effective treatments with minimal side effects. Vincristine sulfate, a potent chemotherapeutic, faces challenges due to P-glycoprotein-mediated resistance and its systemic toxicity. Nanoparticles offer a promising solution by improving pharmacokinetics, targeting tumor cells, thus reducing side effects. Moreover, the use of fluorescent nanomaterials is emerging in biomedical applications such as bioimaging, detection and therapies. This study describes a promising delivery system utilizing carbon dots encapsulated with vincristine in biodegradable polycaprolactone nanoparticles via a double emulsion technique. The fine characterization of these nanoparticles showed that they are spherical, uniformly sized with around 200 nm and exhibit excellent colloidal stability. Moreover, the release profile showed prolonged release for both vincristine and carbon dots. In vitro cell viability studies revealed enhanced cancer cell inhibition for the encapsulated drug compared to the vincristine solution. The uptake study indicated clear fluorescence for carbon dots solution and vincristine and carbon dots loaded nanoparticles upon excitation. Additionally, studies on primary mouse hepatocytes demonstrated higher fluorescence intensity in treatment groups. These results suggest that vincristine and carbon dots loaded nanoparticles are effective, target-specific carriers for liver cancer treatment. Furthermore, the carbon dots were not cytotoxic, highlighting their potential in bioimaging and cancer cell studies. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Low‐Quality Indian Coal Derived Fluorescent Carbon Nano‐Onions for Tissue Imaging.
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Mandal, Tuhin, Rag Mishra, Shiv, Banerjee, Abhishek, Firoz, Ghazal, Poddar, Raju, and Singh, Vikram
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OPTICAL coherence tomography , *CONTRAST media , *COLLOIDAL stability , *SURFACE defects , *HYDROXYL group - Abstract
The synthesis of novel contrast agents based on carbon nanomaterials is garnering significant attention because of their unique properties, such as biocompatibility, ease of fabrication, colloidal stability, and low cost. This article describes a possible and sustainable approach for developing blue‐emitting fluorescent carbon nano‐onions from low‐quality Indian coal using simple mild acid oxidation. The high‐resolution transmission electron micrograph of prepared carbon nanomaterials reveals the crystalline graphitic and multilayer nano‐onion morphology, further supported by Raman and X‐ray diffraction study. Optical coherence tomography was used to capture the tissue image by employing carbon nano‐onions as a contrast agent. The surface defect caused by the carboxylic and hydroxyl functional groups of fluorescent carbon nano‐onions enhances the contrast by increasing the backscattering signal received from the deeper regions in the tissue sample. The transmission electron microscopic study and tunable emission property of carbon nano‐onions confirmed the different sizes of carbon nano‐onions, which also play a crucial role in backscattering. This inventive approach for producing large‐scale fluorescent carbon nano‐onions from low‐quality Indian coal opens up new possibilities for the economical and sustainable development of contrast agents for biomedical imaging. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Phytoglycogen Nanolubricants with Extended Retention Time in Joints.
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Ma, Yingshan, Nouri, Shahrzad, Pham, Duy Anh, Ziyaeyan, Atoosa, Chen, Zhengkun, Morozova, Sofia, Chekini, Mahshid, Banquy, Xavier, Adibnia, Vahid, Viswanathan, Sowmya, and Kumacheva, Eugenia
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RF values (Chromatography) , *COLLOIDAL stability , *HYALURONIC acid , *CARTILAGE , *CHRONIC diseases - Abstract
Osteoarthritis is a prevalent chronic health condition that is mostly associated with the degeneration of joint cartilage due to aging or abnormal mechanical stress in the joint. Intraarticularly injected nanoparticle‐based lubricants decrease the friction between damaged cartilage surfaces, thus preventing their further degradation; however, the effectiveness of currently used nanoparticle‐based lubricants is limited by their short retention time in the joint space. To address this challenge, cationically modified biosourced phytoglycogen nanolubricants are utilized, which electrostatically bind to the cartilage components. The conjugation of the nanoparticles with red‐emissive fluorescent carbon dots enables in vivo studies of their retention in the joint. The hytoglycogen nanoconjugates exhibit high colloidal stability in physiological conditions, provide a friction coefficient of 10−3–10−2 between the sliding surfaces under physiologically relevant pressures, strongly bind to the major cartilage surface components, and show significantly prolonged retention time in the joint in vivo, with a fourfold increase in half‐life in comparison with conventionally used hyaluronic acid injectant. These properties make these functionalized phytoglycogen nanoparticles a highly promising candidate for joint lubrication. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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12. Revealing the Structural Intricacies of Biomembrane‐Interfaced Emulsions with Small‐ and Ultra‐Small‐Angle Neutron Scattering.
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Vidallon, Mark Louis P., Williams, Ashley P., Moon, Mitchell J., Liu, Haikun, Trépout, Sylvain, Bishop, Alexis I., Teo, Boon Mian, Tabor, Rico F., Peter, Karlheinz, de Campo, Liliana, and Wang, Xiaowei
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SCATTERING (Physics) , *NEUTRON scattering , *DEUTERIUM oxide , *ERYTHROCYTES , *COLLOIDAL stability - Abstract
Utilizing cell membranes from diverse cell types for biointerfacing has demonstrated significant advantages in enhancing colloidal stability and incorporating biological properties, tailored specifically for various biomedical applications. However, the structures of these materials, particularly emulsions interfaced with red blood cell (RBC) or platelet (PLT) membranes, remain an underexplored area. This study systematically employs small‐ and ultra‐small‐angle neutron scattering (SANS and USANS) with contrast variation to investigate the structure of emulsions containing perfluorohexane within RBC (RBC/PFH) and PLT membranes (PLT/PFH). The findings reveal that the scattering length density of RBC and PLT membranes is 1.5 × 10−6 Å−2, similar to 30% (w/w) deuterium oxide. Using this solvent as a cell membrane‐matching medium, estimated droplet diameters are 770 nm (RBC/PFH) and 1.5 µm (PLT/PFH), based on polydispersed sphere model fitting. Intriguingly, calculated patterns and invariant analysis reveal native droplet architectures featuring entirely liquid PFH cores, differing significantly from the observed bubble–droplet core system in electron microscopy. This highlights the advantage of SANS and USANS in differentiating genuine colloidal structures in complex dispersions. In summary, this work underscores the pivotal role of SANS and USANS in characterizing biointerfaced colloids and in uncovering novel colloidal structures with significant potential for biomedical applications and clinical translation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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13. From Corrosion Casting to Virtual Dissection: Contrast‐Enhanced Vascular Imaging using Hafnium Oxide Nanocrystals.
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Goossens, Eline, Deblock, Loren, Caboor, Lisa, Eynden, Dietger Van den, Josipovic, Iván, Isaacura, Pablo Reyes, Maksimova, Elizaveta, Van Impe, Matthias, Bonnin, Anne, Segers, Patrick, Cornillie, Pieter, Boone, Matthieu N., Van Driessche, Isabel, De Spiegelaere, Ward, De Roo, Jonathan, Sips, Patrick, and De Buysser, Klaartje
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X-ray computed microtomography , *HAFNIUM oxide , *COMPUTED tomography , *CARDIOVASCULAR system , *COLLOIDAL stability - Abstract
Vascular corrosion casting is a method used to visualize the three dimensional (3D) anatomy and branching pattern of blood vessels. A polymer resin is injected in the vascular system and, after curing, the surrounding tissue is removed. The latter often deforms or even fractures the fragile cast. Here, a method is proposed that does not require corrosion, and is based on in situ micro computed tomography (micro‐CT) scans. To overcome the lack of CT contrast between the polymer cast and the animals' surrounding soft tissue, hafnium oxide nanocrystals (HfO2 NCs) are introduced as CT contrast agents into the resin. The NCs dramatically improve the overall CT contrast of the cast and allow for straightforward segmentation in the CT scans. Careful design of the NC surface chemistry ensures the colloidal stability of the NCs in the casting resin. Using only 5 m% of HfO2 NCs, high‐quality cardiovascular casts of both zebrafish and mice can be automatically segmented using CT imaging software. This allows to differentiate even μ$\umu$m‐scale details without having to alter the current resin injection methods. This new method of virtual dissection by visualizing casts in situ using contrast‐enhanced CT imaging greatly expands the application potential of the technique. [ABSTRACT FROM AUTHOR]
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- 2024
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14. A self‐regulated phototheranostic nanosystem with single wavelength‐triggered energy switching and oxygen supply for multimodal synergistic therapy of bacterial biofilm infections.
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Wang, Cheng, Lv, Shuyi, Sun, Zhencheng, Xiao, Minghui, Fu, Hao, Tian, Liang, Zhao, Xianhao, Shi, Linqi, and Zhu, Chunlei
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REVERSIBLE phase transitions ,PHASE transitions ,BACTERIAL diseases ,COLLOIDAL stability ,COMBINED modality therapy - Abstract
The exploration of antibiotic‐independent phototherapy strategies for the treatment of bacterial biofilm infections has gained significant attention. However, efficient eradication of bacterial biofilms remains a challenge. Herein, a self‐regulated phototheranostic nanosystem with single wavelength‐triggered photothermal therapy (PTT)/photodynamic therapy (PDT) transformation and oxygen supply for multimodal synergistic therapy of bacterial biofilm infections is presented. This approach combines a eutectic mixture of natural phase‐change materials (PCMs) and an aggregation‐induced emission (AIE) phototheranostic agent TPA‐ICN to form colloidally stable nanopartcicles (i.e. AIE@PCM NPs). The reversible solid−liquid phase transition of PCMs facilitates the adaptive regulation of the aggregation states of TPA‐ICN, enabling a switch between the energy dissipation pathways for enhanced PDT in solid PCMs or enhanced PTT in liquid PCMs. Additionally, oxygen‐carrying thermoresponsive nanoparticles are also introduced to alleviate the hypoxic microenvironment of biofilms by releasing oxygen upon heating by AIE@PCM NPs with enhanced PTT. The nanosystem exhibits outstanding therapeutic efficacy against bacterial biofilms both in vitro and in vivo, with an antibacterial efficiency of 99.99%. This study utilizes a self‐regulated theranostic nanoplatform with adaptive PTT/PDT transformation via the phase transition of PCMs and heat‐triggered oxygen release, holding great promise in the safe and efficient treatment of bacterial biofilm infections. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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15. New Proline-Specific Endoprotease for Improved Colloidal Beer Stability and Gluten Reduction.
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Cramer, Jacob F., Bladt, Tove, Fratianni, Andrew, Schoenenberg, Sven, and Eiken, Jens
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COLLOIDAL stability ,TRICHODERMA reesei ,RAW materials ,PROLINE ,ENZYMES ,GLUTEN - Abstract
Chill-haze is a well-known concern for brewers and most commonly involves polyphenols that interact with proline-rich hordein proteins in beers. An effective haze-suppressing effect has previously been established by a proline-specific endoprotease (PEP). In the present study, the protease action of a new Trichoderma reesei expressed PEP enzyme, available as the product BCLEAR
™ was studied by assessing its impact on colloidal as well as foam stability and gluten reduction in beer. All malt beers treated with the BCLEAR™ enzyme or beers produced using BCLEAR™ at low dosage levels during fermentation, showed improved colloidal and foam stability when compared to the benchmark PEP investigated. In addition, gluten reduction was investigated using the BCLEAR™ enzyme and was found to have a very good correlation with the observed haze reduction, suggesting that the PEP enzyme dosage can accurately be determined from the calculated gluten content of the given raw materials. Thus, for optimal PEP enzyme use, the brew processes may most efficiently be controlled by following the gluten content, which was demonstrated with use of Lateral Flow Device (LFD) analysis technology. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
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16. Highly Water-Dispersed Natural Fullerenes Coated with Pluronic Polymers as Novel Nanoantioxidants for Enhanced Antioxidant Activity.
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Oh, Hyeryeon, Lee, Jin Sil, Son, Panmo, Sim, Jooyoung, Park, Min Hee, Bang, Young Eun, Sung, Daekyung, Lim, Jong-Min, and Choi, Won Il
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REACTIVE oxygen species ,COLLOIDAL stability ,RADICALS (Chemistry) ,OXIDATIVE stress ,POLYMERS - Abstract
Fullerene is a cosmic material with a buckyball-like structure comprising 60 carbon atoms. It has attracted significant interest because of its outstanding antioxidant, antiviral, and antibacterial properties. Natural fullerene (NC60) in shungite meets the demand of biomedical fields to scavenge reactive oxygen species in many diseases. However, its hydrophobicity and poor solubility in water hinder its use as an antioxidant. In this study, highly water-dispersed and stable Pluronic-coated natural fullerene nanoaggregates (NC60/Plu) were prepared from various Pluronic polymers. The water dispersity and stability of NC60 were compared and optimized based on the characteristics of Pluronic polymers including F68, F127, L35, P123, and L81. In particular, NC60 coated with Pluronic F127 at a weight ratio of 1 to 5 showed excellent antioxidant effects both in situ and in vitro. This suggests that the high solubilization of NC60 in Pluronic polymers increases its chance of interacting with reactive oxygen radicals and improves radical scavenging activity. Thus, the optimized NC60/PF127 may be a novel biocompatible antioxidant for treating various diseases associated with oxidative stress. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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17. Near‐Infrared Afterglow Luminescence Amplification via Albumin Complexation of Semiconducting Polymer Nanoparticles for Surgical Navigation in Ex Vivo Porcine Models.
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Bendele, Nathaniel, Kitamura, Ken, Vasquez, Isabella, Harun, Asma, Carroll, McKenzie, and Srivastava, Indrajit
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SERUM albumin , *COLLOIDAL stability , *ONCOLOGIC surgery , *MOLECULAR docking , *LUMINESCENCE - Abstract
Afterglow imaging, leveraging persistent luminescence following light cessation, has emerged as a promising modality for surgical interventions. However, the scarcity of efficient near‐infrared (NIR) responsive afterglow materials, along with their inherently low brightness and lack of cyclic modulation in afterglow emission, has impeded their widespread adoption. Addressing these challenges requires a strategic repurposing of afterglow materials that improve on such limitations. Here, an afterglow probe, composed of bovine serum albumin (BSA) coated with an afterglow material, a semiconducting polymer dye (SP1), called BSA@SP1 demonstrating a substantial amplification of the afterglow luminescence (≈3‐fold) compared to polymer‐lipid coated PFODBT (DSPE‐PEG@SP1) under same experimental conditions is developed. This enhancement is believed to be attributed to the electron‐rich matrix provided by BSA that immobilizes SP1 and enhances the generation of 1O2 radicals, which improves the afterglow luminescence brightness. Through molecular docking, physicochemical characterization, and optical assessments, BSA@SP1's superior afterglow properties, cyclic afterglow behavior, long‐term colloidal stability, and biocompatibility are highlighted. Furthermore, superior tissue permeation profiling of afterglow signals of BSA@SP1's compared to fluorescence signals using ex vivo tumor‐mimicking phantoms and various porcine tissue types (skin, muscle, and fat) is demonstrated. Expanding on this, to showcase BSA@SP1's potential in image‐guided surgeries, tumor‐mimicking phantoms within porcine lungs and conducted direct comparisons between fluorescence and afterglow‐guided interventions to illustrate the latter's superiority is implanted. Overall, the study introduces a promising strategy for enhancing current afterglow materials through protein complexation, resulting in both ultrahigh signal‐to‐background ratios and cyclic afterglow signals. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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18. Organic Donor–Acceptor–Donor Trimers Nanoparticles Stabilized by Amphiphilic Block Copolymers for Photocatalytic Generation of H2.
- Author
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Guimarães, Thiago R., Khan, Alisha, Remita, Hynd, Bobet, Jean‐Louis, and Cloutet, Eric
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GREEN fuels , *PHOTOCATALYSTS , *COLLOIDAL stability , *ECOLOGICAL impact , *INTERSTITIAL hydrogen generation - Abstract
Photocatalytic generation of H2 via water splitting emerges as a promising avenue for the next generation of green hydrogen due to its low carbon footprint. Herein, a versatile platform is designed to the preparation of functional π‐conjugated organic nanoparticles dispersed in aqueous phase via mini‐emulsification. Such particles are composed of donor–acceptor–donor (DAD) trimers prepared via Stille coupling, stabilized by amphiphilic block copolymers synthesized by reversible addition‐fragmentation chain transfer polymerization. The hydrophilic segment of the block copolymers will not only provide colloidal stability, but also allow for precise control over the surface functionalization. Photocatalytic tests of the resulting particles for H2 production resulted in promising photocatalytic activity (≈0.6 mmol g−1 h−1). This activity is much enhanced compared to that of DAD trimers dispersed in the water phase without stabilization by the block copolymers. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
19. Organic Donor–Acceptor–Donor Trimers Nanoparticles Stabilized by Amphiphilic Block Copolymers for Photocatalytic Generation of H2.
- Author
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Guimarães, Thiago R., Khan, Alisha, Remita, Hynd, Bobet, Jean‐Louis, and Cloutet, Eric
- Subjects
GREEN fuels ,PHOTOCATALYSTS ,COLLOIDAL stability ,ECOLOGICAL impact ,INTERSTITIAL hydrogen generation - Abstract
Photocatalytic generation of H2 via water splitting emerges as a promising avenue for the next generation of green hydrogen due to its low carbon footprint. Herein, a versatile platform is designed to the preparation of functional π‐conjugated organic nanoparticles dispersed in aqueous phase via mini‐emulsification. Such particles are composed of donor–acceptor–donor (DAD) trimers prepared via Stille coupling, stabilized by amphiphilic block copolymers synthesized by reversible addition‐fragmentation chain transfer polymerization. The hydrophilic segment of the block copolymers will not only provide colloidal stability, but also allow for precise control over the surface functionalization. Photocatalytic tests of the resulting particles for H2 production resulted in promising photocatalytic activity (≈0.6 mmol g−1 h−1). This activity is much enhanced compared to that of DAD trimers dispersed in the water phase without stabilization by the block copolymers. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
20. One‐Step DES‐Mediated Synthesis of Au Nanoparticles Using Eysenhardtia polystachya Extract and Evaluation of Their Proapoptotic and Anti‐Inflammatory Activities.
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Gutiérrez‐Sánchez, Roxana, Molina, Gustavo A., López‐Miranda, J. Luis, Rodríguez‐Torres, Angelina, Estévez, Miriam, and Esparza, Rodrigo
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SCANNING transmission electron microscopy , *FOURIER transform infrared spectroscopy , *GOLD nanoparticles , *PLANT extracts , *COLLOIDAL stability - Abstract
The synthesis of nanomaterials using plant extracts is considered to be a safer, environmentally friendly, and cost‐effective alternative method. In this work, Eysenhardtia polystachya (EP) extract and choline chloride/urea (ChCl/urea)‐based deep eutectic solvent (DES) were used for the synthesis of gold nanoparticles (AuNPs), without an additional stabilizing agent, which is of great interest in the field of biomedicine. The antioxidant capacity of the extract and the phenolic content, involved in the reduction of Au3+ ions of the precursor were evaluated. The AuNPs were characterized by ultraviolet‐visible spectroscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, dynamic light scattering, ζ‐potential, confocal laser scanning microscopy, scanning and transmission electron microscopy. The nanoparticles are mostly quasi‐spherical shape, with a multiply‐twinned structure, an average particle size of 36 nm, and a characteristic absorption peak at 545 nm. The colloidal stability was confirmed with a ζ‐potential value of −32.8 mV. Finally, the AuNPs were tested for their potential in cancer therapy using human prostate adenocarcinoma PC‐3 cells. The anti‐inflammatory activity of the EP extract and AuNPs was also evaluated. The results showed that the synthesized AuNPs could potentially induce cell death and have an anti‐inflammatory effect. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Customizable Induction Heating Profiles: from Tailored Colloidally Stable Nanoparticles Toward Multi‐Stage Heatable Supraparticles.
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Luthardt, Leoni, Raczka, Theodor, Hurle, Katrin, Müssig, Stephan, and Mandel, Karl
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IRON oxide nanoparticles , *MANUFACTURING processes , *SPECIFIC heat , *INDUCTION heating , *COLLOIDAL stability - Abstract
Magnetic nanoparticles (NPs) are efficient heat mediators in induction heating. Originally explored for hyperthermia, their applications have broadened to industrial processes where temperature control is crucial. By adjusting the NP composition or morphology, magnetic characteristics such as Curie temperatures can be tailored, allowing control over maximum heating thresholds. These NPs are, however, usually designed for maximum heating rates at specific magnetic fields. In this work, the synthesis is presented for colloidally stable Co and ZnCo ferrite NPs with customizable maximum heating temperatures, and their combination within micron‐scaled supraparticles (SPs). Maximum induction heating temperatures of ZnCo ferrite NPs are tuned between 150 and 220 °C, while customization of Co ferrite species yields temperatures between 200 and 350 °C. These distinct magnetic properties are exploited in the selective multi‐stage heating of SPs consisting of both species. Here, ZnCo ferrite components heat up to a first temperature plateau at low alternating magnetic fields (AMF), while Co ferrite NPs reach higher temperatures at increased AMF. The precise control of induction heating thresholds through the adaptability of NPs offers a high degree of customizability which makes induction heating particularly attractive for applications requiring sequential or spatial heating, such as catalysis or debonding on demand. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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22. Hybrid lipid-AuNP clusters as highly efficient SERS substrates for biomedical applications.
- Author
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Cardellini, Jacopo, Dallari, Caterina, De Santis, Ilaria, Riccio, Lorenzo, Ceni, Costanza, Morrone, Amelia, Calamai, Martino, Pavone, Francesco Saverio, Credi, Caterina, Montis, Costanza, and Berti, Debora
- Subjects
SERS spectroscopy ,GOLD nanoparticles ,GOLD clusters ,COLLOIDAL stability ,ELECTROMAGNETIC fields - Abstract
Although Surface Enhanced Raman Scattering (SERS) is widely applied for ultrasensitive diagnostics and imaging, its potential is largely limited by the difficult preparation of SERS tags, typically metallic nanoparticles (NPs) functionalized with Raman-active molecules (RRs), whose production often involves complex synthetic approaches, low colloidal stability and poor reproducibility. Here, we introduce LipoGold Tags, a simple platform where gold NPs (AuNPs) clusters form via self-assembly on lipid vesicle. RRs embedded in the lipid bilayer experience enhanced electromagnetic field, significantly increasing their Raman signals. We modulate RRs and lipid vesicle concentrations to achieve optimal SERS enhancement and we provide robust structural characterization. We further demonstrate the versatility of LipoGold Tags by functionalizing them with biomolecular probes, including antibodies. As proof of concept, we successfully detect intracellular GM1 alterations, distinguishing healthy donors from patients with infantile GM1 gangliosidosis, showcasing LipoGold Tags as advancement in SERS probes production. Surface Enhanced Raman Scattering (SERS) detection is often limited by difficulties in preparing adequate tags – normally metallic nanoparticles (NPs) functionalised with Raman-active molecules. Here, the authors introduce LipoGold Tags, a platform where clusters of gold NPs self-assemble on lipid vesicles. These tags are used for SERS detection. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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23. Evaluation of PVC@Silver Nanocomposite as Sensor for Low Limit Detection of Cadmium Ion By Surface Plasmon Resonance Based Method.
- Author
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Ali, Safaa S., Ebnalwaled, A. A., Mohamed, Gehad G., and Hafez, M.
- Subjects
- *
SURFACE plasmon resonance , *SILVER nanoparticles , *NANOPARTICLE size , *BAND gaps , *COLLOIDAL stability - Abstract
This study explores the development of a PVC@Silver nanocomposite for enhanced detection of cadmium ions in water samples. Various characterization techniques confirmed the successful incorporation of silver nanoparticles into the polyvinyl chloride (PVC) matrix across different concentrations (1–4%). X-ray diffraction revealed the face-centered cubic crystalline structure of the silver nanoparticles, with the intensities of the (111), (200), (220), and (311) peaks increasing with higher Ag concentrations. The average crystallite sizes ranged from 26.1 nm (3% Ag) to 30.0 nm (2% Ag). Dynamic light scattering showed nanoparticle sizes of 24–43 nm, while zeta potential values of -24 to -40 mV indicated reasonable colloidal stability. Brunauer–Emmett–Teller (BET) surface area analysis demonstrated a decreasing surface area from 30.09 m2/g (1% Ag) to 25.27 m2/g (3% Ag), attributed to pore filling by silver nanostructures. Significantly, the PVC@Silver nanocomposite facilitated sensitive detection of Cd(II) ions using surface plasmon resonance (SPR), exhibiting an SPR angle shift of 26.30° with intensity values ranging from 10.80 (4% Ag) to 12.19 (3% Ag). UV–vis spectra revealed a prominent surface plasmon resonance band at 420–430 nm, indicating the presence of silver nanoparticles. The optical band gap varied from 4.51eV (1% Ag) to 4.12eV (4% Ag). [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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24. Optical imaging and gene transfection potential of linear polyethylenimine-coated Ag2S near-infrared quantum dots.
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SAVALAN, Altay
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- *
GREEN fluorescent protein , *CANCER genes , *GENE transfection , *COLLOIDAL stability , *MYELOID sarcoma , *QUANTUM dots , *GENETIC vectors - Abstract
Background/aim: The application of biocompatible heavy metal-free and cationic Ag2S NIR quantum dots (QDs), which have intense luminosity in the 700-900 nm medical range, as a nonviral gene delivery system paves the way to overcome autofluorescence and easily track the delivery of genes in real time. Materials and methods: The newly developed small and colloidally stable 2-mercaptopropionic acid (MPA)-capped Ag2S aqueous quantum dots electrostatically complexed with linear polyethyleneimine (Ag2S@2MPA/LPEI) were investigated for the first time both as a strong fluorescent probe and as a vector for nonviral gene delivery for the highest tracking of the system and delivery of genes into the nuclei of different cancer cells. The synthesized Ag2S@2MPA/LPEI quantum dots demonstrated strong optical imaging properties and were used to deliver a green fluorescent protein (GFP) plasmid as a standard gene. Results: For Ag2S@2MPA/LPEI-pDNA nanoparticles, an N/P ratio of 20 was the ideal transfection efficiency. Ag2S@2MPA/LPEI was substantially more compatible with HEK 293T cells than the free 25-kDa linear polyethylenimine (LPEI). Next, the transfection efficiency evaluation of pGFP genes with synthesized Ag2S@2MPA/LPEI and LPEI in different cancer cells demonstrated their high potential as a theranostic cancer gene delivery system. Conclusion: This is the first instance of gene transfection and optical imaging carried out in vitro using Ag2S@2MPA/LPEI QDs. Overall, the newly synthesized highly biocompatible and trackable Ag2S@2MPA/LPEI QDs can be an effective and biocompatible theranostic system for cancer gene therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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25. Adaptable Self‐Assembly of a PEG Dendrimer‐Coiled Coil Conjugate.
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Lee, Young‐joo, Jung, You‐jin, and Lim, Yong‐beom
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CIRCULAR dichroism , *STERIC hindrance , *COLLOIDAL stability , *PEPTIDES , *SURFACE potential - Abstract
Self‐assembly of designed molecules has enabled the construction of a variety of functional nanostructures. Specifically, adaptable self‐assembly has demonstrated several advantageous features for smart materials. Here, we demonstrate that an α‐helical coiled coil conjugated with a dendrimer can adapt to spatial restriction due to the strong steric repulsion between dendrimer chains. The adaptable transformation of a tetrameric coiled coil to a trimeric coiled coil can be confirmed using analytical ultracentrifugation upon conjugation of the dendrimer to the coiled coil‐forming building block. Interestingly, circular dichroism spectroscopy analysis of the dendrimer conjugate revealed an unconventional trend: the multimerization of the coiled coil is inversely dependent on concentration. This result implies that the spatial crowding between the bulky dendritic chains is significantly stronger than that between linear chains, thereby affecting the overall assembly process. We further illustrated the application potential by decorating the surface of gold nanorods (AuNRs) with the adaptable coiled coil. The dendrimer‐coiled coil peptide conjugate can be utilized to fabricate organic‐inorganic nanohybrids with enhanced colloidal and thermal stabilities. This study demonstrates that the coiled coil can engage in the adaptable mode of self‐assembly with the potential to form dynamic peptide‐based materials. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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26. Ligand compensation enabling efficient and stable exciton recombination in perovskite QDs for high-performance QLEDs.
- Author
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Wang, Jindi, Li, Mingyang, Fan, Wenxuan, Xu, Leimeng, Yao, Jisong, Wang, Shalong, and Song, Jizhong
- Subjects
- *
QUANTUM efficiency , *QUANTUM dot LEDs , *LIGHT emitting diodes , *COLLOIDAL stability , *OPTOELECTRONICS - Abstract
Perovskite quantum dot-based light-emitting diodes (QLEDs) have been considered as a promising luminescent technology due to high color purity and wide color gamut. However, the realization of high-performance QLED is still hindered by near-perfect quantum dots (QDs) with efficient and stable exciton recombination behavior. Here, we proposed a ligand compensation (LC) strategy to optimize the QDs by introducing a ligand pair of tri-n-octylphosphine (TOP) and CsBr. The ligand pair could enhance the clarity and colloidal stability of the QD ink, facilitating the fabrication of highly smooth films. On one hand, TOP engages in interactions with Pb and effectively passivates the surface uncoordinated Pb2+. On the other hand, the supplement of CsBr provides a Br-rich environment to reduce Br vacancies (VBr). Through LC, QD films possess a high photoluminescence quantum efficiency of 82% and a shallow hole level, which enables efficient exciton recombination. In addition, the LC makes QD films exhibit stable exciton combination behavior and electrical transport characteristics. Resultantly, the LC-optimized QLEDs show a maximum external quantum efficiency (EQE) of 24.7% and an operational lifetime T50 of 182 h at an initial luminance of 100 cd m−2, which is obviously higher than that of the control device (EQE of 15.8%, T50 of 11 h). The proposed LC strategy for optimizing perovskite QDs presents a novel concept for achieving high-performance QLEDs and holds great potential for widespread application in various optoelectronics. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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27. Improvement in the Photocatalytic Hydrogen Production of Flower-Shaped ZnIn 2 S 4 by Surface Modification with Amino Silane.
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Chen, Xiangyu, Liang, Benliang, and Yan, Luting
- Subjects
- *
INTERSTITIAL hydrogen generation , *HYDROGEN production , *BAND gaps , *PHOTOCATALYSTS , *COLLOIDAL stability - Abstract
ZnIn2S4 has attracted extensive attention in the field of photocatalytic hydrogen production because of its suitable band gap and excellent photoelectrochemical properties. However, its lower photogenerated carrier separation efficiency and high degree of photocorrosion severely restricts its photocatalytic activity. In this work, the photocatalytic hydrogen production performance of ZnIn2S4 modified with 3-aminopropylmethoxysilane was studied. Surface modification by amino silane not only regulated the band gap and enhanced the light absorption of ZnIn2S4 but it also increased the colloidal stability of the ZnIn2S4 suspension and enhanced the adsorption of H+ on the active surface sites, thereby improving the photocatalytic hydrogen production performance. Compared with that of unmodified ZnIn2S4, the photocatalytic hydrogen production rate of surface-modified ZnIn2S4 increased by 1.46 times, and after four cycles for 12 h, the hydrogen production efficiency remained at 75.14%. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
28. Highly Specific Polyphenolic Colloids as Alternatives to Antimicrobials in Livestock Production.
- Author
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Laconi, Andrea, Cecconello, Alessandro, Molinari, Simone, Rilievo, Graziano, Cencini, Aura, Tonolo, Federica, Krystofova, Antonie, Majethia, Hardik Nilesh, Tolosi, Roberta, Schiavon, Eliana, Nicoletto, Carlo, Piccirillo, Alessandra, Vianello, Fabio, and Magro, Massimiliano
- Subjects
- *
ESCHERICHIA coli , *COLLOIDAL suspensions , *COLLOIDAL stability , *PHENOLS , *CHEMICAL stability - Abstract
The dispersion of antibiotics in livestock farming represents a health concern worldwide, contributing to the spread of antimicrobial-resistant bacteria through animals, the environment, and humans. Phenolic compounds could be alternatives to antibiotics, once drawbacks such as their low water solubility, bioavailability, and reduced stability are overcome. Although nano- or micro-sized formulations could counter these shortcomings, they do not represent cost-effective options. In this study, three phenolic compounds, obtained from wood-processing manufacturers, were characterized, revealing suitable features such as their antioxidant activity, size, and chemical and colloidal stability for in-field applications. The minimum inhibitory concentration (MIC) of these colloidal suspensions was measured against six bacterial strains isolated from livestock. These particles showed different inhibition behaviors: Colloidal chestnut was effective against one of the most threatening antibiotic-resistant pathogens, i.e., S. aureus, but ineffective toward E. coli. Instead, colloidal pine showed a weak effect on S. aureus but specificity toward E. coli. The present proof-of-concept points at colloidal polyphenols as valuable alternatives for antimicrobial substitutes in the livestock context. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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29. Design and preparation of pH-sensitive cytotoxic liposomal formulations containing antitumor colchicine analogues for target release.
- Author
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Shchegravina, Ekaterina S., Tretiakova, Daria S., Sitdikova, Alsu R., Usova, Sofia D., Boldyrev, Ivan A., Alekseeva, Anna S., Svirshchevskaya, Elena V., Vodovozova, Elena L., and Fedorov, Alexey Yu.
- Subjects
- *
PRODRUGS , *COLCHICINE , *COLLOIDAL stability , *LIPOSOMES , *TUMOR microenvironment , *ANTINEOPLASTIC agents - Abstract
Herein, we describe the synthesis of pH-sensitive lipophilic colchicine prodrugs for liposomal bilayer inclusion, as well as preparation and characterization of presumably stealth PEGylated liposomes with above-mentioned prodrugs. These formulations liberate strongly cytotoxic colchicinoid derivatives selectively under slightly acidic tumor-associated conditions, ensuring tumor-targeted delivery of the compounds. The design of the prodrugs is addressed to pH-triggered release of active compounds in the slight acidic media, that corresponds to tumor microenvironment, while keeping sufficient stability of the whole formulation at physiological pH. Correlations between the structure of the conjugates, their hydrolytic stability, colloidal stability, ability of the prodrug retention in the lipid bilayer are described. Several formulations were found promising for further development and in vivo investigations. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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30. Zwitterionic nanoparticles from indocyanine green dimerization for imaging-guided cancer phototherapy.
- Author
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Feng, Wenbi, Mu, Xueluer, Li, Yajie, Sun, Shi, Gao, Min, Lu, Yingxi, and Zhou, Xianfeng
- Subjects
CRITICAL micelle concentration ,INDOCYANINE green ,LASER ablation ,REACTIVE oxygen species ,COLLOIDAL stability - Abstract
Indocyanine green (ICG), the only near-infrared (NIR) dye approved for clinical use, has received increasing attention as a theranostic agent wherein diagnosis (fluorescence) is combined with therapy (phototherapy), but suffers rapid hepatic clearance, poor photostability, and limited accumulation at tumor sites. Here we report that dimerized ICG can self-assemble to form zwitterionic nanoparticles (ZN-dICG), which generate fluorescence self-quenching but exhibit superior photothermal and photodynamic properties over ICG. The zwitterionic moieties confer ZN-dICG an ultralow critical micelle concentration and high colloidal stability with low non-specific binding in vivo. In addition, ZN-dICG can respond to the over-generated reactive oxygen species (ROSs) and dissociate to restore NIR fluorescence of ICG, amplifying the sensitivity via albumin binding for low-background imaging of tumors. Following systemic administration, ZN-dICG accumulated in tumors of xenograft-bearing mice for imaging primary and metastatic tumors, and induced tumor ablation under laser irradiation. The discovery of ZN-dICG would contribute to the design of translational phototheranostic platform with high biocompatibility. Indocyanine green (ICG) has been extensively studied as a phototheranostic agent that combines imaging with phototherapies, but it suffers from rapid hepatic clearance, poor photostability, and limited accumulation at tumor sites. Here, we report a strategy to construct ICG dimers (ICG-tk-ICG) by conjugating two ICG molecules via a thioketal bond, which can self-assemble into zwitterionic nanoparticles (ZN-dICG) at ultralow critical micelle concentrations, exhibiting superior photothermal and photodynamic properties over ICG. ZN-dICG responds to the over-generated ROS in tumors and dissociates to restore the NIR fluorescence of ICG, enhancing the sensitivity via albumin binding for low-background imaging of tumors. This study offers a supramolecular strategy that may potentiate the clinical translation of ICG in imaging-guided cancer phototherapy. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2024
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31. Dual-functionalized architecture enables stable and tumor cell-specific SiO2NPs in complex biological fluids
- Author
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Iris Renata Sousa Ribeiro, Raquel Frenedoso da Silva, Romênia Ramos Domingues, Adriana Franco Paes Leme, and Mateus Borba Cardoso
- Subjects
colloidal stability ,complex media ,functionalized nanoparticles ,hemolysis ,targeting tumor ,Technology ,Chemical technology ,TP1-1185 ,Science ,Physics ,QC1-999 - Abstract
Most commercial anticancer nanomedicines are administered intravenously. This route is fast and precise as the drug enters directly into the systemic circulation, without undergoing absorption processes. When nanoparticles come into direct contact with the blood, however, they interact with physiological components that can induce colloidal destabilization and/or changes in their original biochemical identity, compromising their ability to selectively accumulate at target sites. In this way, these systems usually lack active targeting, offering limited therapeutic effectiveness. In the literature, there is a paucity of in-depth studies in complex environments to evaluate nanoparticle stability, protein corona formation, hemolytic activity, and targeting capabilities. To address this issue, fluorescent silica nanoparticles (SiO2NPs) are here functionalized with zwitterionic (kinetic stabilizer) and folate groups (targeting agent) to provide selective interaction with tumor cell lines in biological media. The stability of these dually functionalized SiO2NPs is preserved in unprocessed human plasma while yielding a decrease in the number of adsorbed proteins. Experiments in murine blood further proved that these nanoparticles are not hemolytic. Remarkably, the functionalized SiO2NPs are more internalized by tumor cells than their healthy counterparts. Investigations of this nature play a crucial role in garnering results with greater reliability, allowing the development of nanoparticle-based pharmaceutical drugs that exhibit heightened efficacy and reduced toxicity for medical purposes.
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- 2024
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32. Experimental techniques for quantifying interactions of polymer-coated particles and surfaces: Insights for material design and optimization
- Author
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Yinan Li and To Ngai
- Subjects
Colloidal stability ,Atomic force microscope ,Total internal reflection microscopy ,Optical tweezers ,Quartz crystal microbalance with dissipation monitoring ,Chemistry ,QD1-999 ,Physics ,QC1-999 - Abstract
Polymer-coated particles and surfaces have widespread applications in various industries ranging from manufacturing to biomedicine. A better understanding of the stability mechanisms underlying these coatings can inspire the design of novel polymer structures and help tune their functions. This can be achieved by quantifying the particle-particle and particle-surface interactions. This paper reviews several common experimental techniques utilized to measure the interactions between polymer-coated particles and surfaces quantitatively. These techniques include atomic force microscopy (AFM), total internal reflection microscopy (TIRM), optical tweezers (OT), and quartz crystal microbalance with dissipation monitoring (QCM-D). The examples of each measuring technique were categorized based on the types of polymer coatings and their associated factors. Additionally, this review demonstrates experimental measurements of interactions involving biological objects. By understanding the fundamental particle-particle and particle-surface interactions, researchers can gain valuable insights to guide the design and functional optimization of polymer-based materials and systems across various applications.
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- 2024
- Full Text
- View/download PDF
33. Bio-templated Synthesis of Multi-functional Bimetallic Ag–Cu Nanospheres: Unveiling Therapeutic Potential.
- Author
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Kataria, Monika, Lal, Sant, and Dilbaghi, Neeraj
- Subjects
- *
ZETA potential , *ELECTRON microscope techniques , *TRANSMISSION electron microscopy , *CRYSTAL surfaces , *SCANNING electron microscopy , *COLLOIDAL stability - Abstract
Antimicrobial medicines serve as the bedrock of modern medical practices. Increasing multidrug resistance compromises surgical processes and increases healthcare costs. Therefore, a combinational approach has become a pre-requisite for sustainable medical care. In recent decade, biologically synthesized metallic nanoparticles have emerged as a class of potent antimicrobials. In this study, green synthesized bimetallic silver–copper oxide (Ag–Cu) nanospheres have been prepared using the culture supernatant of the Bacillus subtilis (MTCC 441) bacteria to effectively target infectious microbes. The hydrodynamic diameter of the nanoparticles as depicted by dynamic light scattering (DLS) was 143.5 nm, while the polydispersity index (PI) of 0.367 and zeta potential of −25.2 mV indicated toward uniform size distribution and excellent colloidal stability. The Ag–Cu nanospheres of diameter 22.24 ± 8.01 nm were prepared using the culture supernatant of B. subtilis MTCC 441. High-end techniques such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy revealed the size (22.24 ± 8.01 nm), spherical morphology, crystal structure and surface functionalization of nanospheres, respectively. The antimicrobial potential of the nanospheres was assessed against multidrug-resistant (MDR) bacterial strains while anti-free radical capacity was evaluated through 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and H 2 O 2 free radical inhibition. The anti-inflammatory study was also performed to investigate the biomedical potential of the synthesized Ag–Cu nanosphere. The comprehensive analysis of antimicrobial, anti-oxidative and anti-inflammatory assays presents Ag–Cu nanospheres spheres as suitable candidates to be used in various biomedical applications. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
34. Hydrophobic iron oxide nanoparticles: Controlled synthesis and phase transfer via flash nanoprecipitation.
- Author
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Bandyopadhyay, Sulalit, Zafar, Haroon, Khan, Muhammad Sarmad, Ansar, Reema, Peddis, Davide, Slimani, Sawssen, Bali, Nesrine, Sajid, Zahra, Qazi, Rida e Maria, ur Rehman, Fawad, and Mian, Afsar Ali
- Subjects
- *
IRON oxide nanoparticles , *COLLOIDAL stability , *CYTOTOXINS , *MAGNETIC properties , *FIBROBLASTS - Abstract
Iron oxide nanoparticles (IONPs) synthesized via thermal decomposition find diverse applications in biomedicine owing to precise control of their physico-chemical properties. However, use in such applications requires phase transfer from organic solvent to water, which remains a bottleneck. Through the thermal decomposition of iron oleate (FeOl), we systematically investigate the impact of synthesis conditions such as oleic acid (OA) amount, temperature increase rate, dwell time, and solvent on the size, magnetic saturation, and crystallinity of IONPs. Solvent choice significantly influences these properties, manipulating which, synthesis of monodisperse IONPs within a tunable size range (10-30 nm) and magnetic properties (75 to 42 Am2Kg-1) is obtained. To enable phase transfer of IONPs, we employ flash nanoprecipitation (FNP) for the first time as a method for scalable and precise size control, demonstrating its potential over conventional methods. Poly(lactic-co-glycolic acid) (PLGA)-coated IONPs with hydrodynamic diameter (H d) in the range of 250 nm, high colloidal stability and high IONPs loadings up to 43% were obtained, such physicochemical properties being tuned exclusively by the size and hydrophobicity of starting IONPs. They showed no discernible cytotoxicity in human dermal fibroblasts, highlighting the applicability of FNP as a novel method for the functionalization of hydrophobic IONPs for biomedicine. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
35. Influence of buffer on colloidal stability, microstructure, and rheology of cellulose nanocrystals in hyaluronic acid suspensions.
- Author
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Bose, Akshai, Zakani, Behzad, and Grecov, Dana
- Subjects
- *
CELLULOSE nanocrystals , *COLLOIDAL stability , *BUFFER solutions , *DLVO theory , *DRUG delivery systems - Abstract
[Display omitted] Hyaluronic acid (HA) is a natural biopolymer found in various human tissues, while cellulose nanocrystals (CNCs) extracted from pulp fibers have unique rheological properties and biocompatibility. Due to the superior biomechanical properties of CNC and HA, a CNC-based HA suspension may be useful in biomedical applications. While buffers are an essential constituent of any suspension used for biomedical applications to maintain the desired pH level, they can significantly affect the properties of the suspension, including colloidal stability, microstructure, and rheological characteristics. To our knowledge, this is the first study analyzing the influence of buffer solutions on the suspension characteristics of HA/CNC systems, integrating both theoretical and experimental approaches. The results revealed an alignment between predictions of the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and results from experiments characterizing a buffer-specific trend in colloidal stability. Suspensions with a higher energy barrier showed higher colloidal stability, with a lower tendency for phase separation and agglomerate formations. The microstructural analysis of CNC tactoids in the suspension revealed the existence of the hedgehog defect when dispersed in different buffer solutions. The defect is predicted to be caused by the pH-dependent protonation and deprotonation of HA. Furthermore, steady shear viscometry showed a microstructural-dependent shear viscosity trend, which, in turn, depends on the buffer solution. The study provides novel insights into the microstructural and bulk properties of HA and CNC suspensions in various buffer solutions. The results highlight the importance of solvent choice in tailoring the properties of the suspension for specific biomedical applications. These findings may be helpful in formulating HA and CNC suspensions for different biomedical applications, including drug delivery systems and viscosupplement injections. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
36. Carboxyl-functionalized dual pH/temperature-responsive poly(N-vinylcaprolactam) microgels based on isogenous comonomers for smart window applications.
- Author
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Zhou, Yuze, Lei, Jiaying, Peng, Jing, Ye, Tengling, Wang, Yumeng, Huang, Ruipeng, Zhang, Yubo, Ren, Yonghui, Zhou, Yuhong, and Tang, Dongyan
- Subjects
- *
PHASE transitions , *ELECTROCHROMIC windows , *MICROGELS , *TRANSITION temperature , *INTELLIGENT sensors - Abstract
[Display omitted] Stimuli-responsive poly(N -vinylcaprolactam) (PVCL)-based microgels, which could response to small external environmental changes, have attracted great interests in the fields of biomedicine and nanotechnology. However, the preparation of such microgels meets severe challenge due to their low incorporation efficiency and thermoresponsivity passivation. To address these issues, we select 3-(tert- butoxycarbonyl)- N- vinylcaprolactam (TBVCL), a carboxyl-functionalized VCL derivative, as a comonomer to develop pH/temperature dual-responsive microgels. TBVCL, with a structure similar to VCL, enhances incorporation efficiency and colloidal stability, while reducing thermoresponsivity passivation. The volume phase transition temperature (VPTT) of the microgels can be adjusted over a broad range (19.0–49.5 °C). Notably, the radial swelling ratios of the microgels can be modulated by pH, achieving a maximum swelling ratio of 3. The distinct changes in dissolution-precipitation behavior under different temperatures or pH conditions make these microgels suitable for applications such as smart windows and sensors. Furthermore, this novel approach for fabricating microgels with pH-tunable phase-transition temperatures demonstrates significant potential for the controlled release of nanoparticles (e.g., drugs, catalysts, and quantum dots) and the development of smart nanocrystal-polymer composite sensors. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
37. Surface engineering of metal-organic framework nanoparticles-based miRNA carrier: Boosting RNA stability, intracellular delivery and synergistic therapy.
- Author
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Jin, Weiguang, Li, Xin, Argandona, Sergio Mercado, Ray, Roslyn M, Lin, Marie Karen Tracy Hong, Melle, Francesca, Clergeaud, Gael, Lars Andresen, Thomas, Nielsen, Martin, Fairen‐Jimenez, David, Astakhova, Kira, and Qvortrup, Katrine
- Subjects
- *
NON-coding RNA , *NUCLEIC acids , *PHOTODYNAMIC therapy , *COLLOIDAL stability , *METAL-organic frameworks - Abstract
[Display omitted] • Dual-layers surface engineering of metal–organic frameworks (MOFs) nanoparticles incorporating lipid coating is presented for miRNA efficient delivery, circumventing the pore size limitation of MOFs pore encapsulation. • This layer-by-layer nanostructure sandwiched the miRNA between the MOFs core and lipid surface layer, enhancing stability of miRNA against biodegradation, but also rendering itself with improved colloidal stability, cellular uptake and lysosomal escape. • A versatile approach combines the MOF-based photodynamic therapy, miRNA gene therapy and pre-encapsulated doxorubicin chemotherapy, which synergistically works against cancer cells. MicroRNAs (miRNAs) are small noncoding RNAs that are critical for the regulation of multiple physiological and pathological processes, thus holding great clinical potential. However, the therapeutic applications of miRNAs are severely limited by their biological instability and poor intracellular delivery. Herein, we describe a dual-layers surface engineering strategy to design an efficient miRNA delivery nanosystem based on metal–organic frameworks (MOFs) incorporating lipid coating. The resulting nanoparticle system was demonstrated to protect miRNA from ribonuclease degradation, enhance cellular uptake and facilitate lysosomal escape. These ensured effective miRNA mediated gene therapy, which synergized with MOF-specific photodynamic therapy and pre-encapsulated doxorubicin (Dox) chemotherapy to provide a multifunctional with therapeutic effectiveness against cencer cells The mechanisms of miRNA binding and Dox loading were revealed, demonstrating the potential of the present MOFs surface-engineered strategy to overcome their inherent pore-size restriction for macromolecular miRNA carrying, enableefficient co-delivery. In vitro studies revealed the potential of our multifunctional system for miRNA delivery and the demonstrated the therapeutic effectiveness against cancer cells, thereby providing a versatile all-in-one MOFs strategy for delivery of nucleic acids and diverse therapeutic molecules in synergistic therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
38. Pyrene-functionalized poly(methacrylic acid) acts as an efficient stabilizer for graphene nanoplatelets and facilitates their use in waterborne latex formulations.
- Author
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Li, Xueyuan, Jamali, Mohammed, and Fielding, Lee A.
- Subjects
- *
METHACRYLIC acid , *SMALL molecules , *POLYMERIC nanocomposites , *PYRENE derivatives , *COLLOIDAL stability , *POLYMERS - Abstract
[Display omitted] • Improved stability of graphene nanoplatelets (GNPs) in water. • Enhanced GNP/polymer matrix interface. • Compatible and readily formulated with industrially-relevant waterborne polymer latex. Pyrene derivatives are effective motifs when designing graphene-philic surfactants, enabling the use of hydrophobic graphene-based nanomaterials in waterborne formulations. Hence, novel pyrene end-functionalized polymeric stabilizers show promise for stabilizing aqueous graphene nanomaterial dispersions, and offer benefits over traditional small molecule surfactants. Pyrene end-functionalized poly(methacrylic acid) (Py-PMAA n , where n = 68 to 128) was synthesized by reversible addition-fragmentation chain-transfer (RAFT) polymerization of MAA using a pyrene-containing RAFT chain-transfer agent. These polymers were evaluated as aqueous graphene nanoplatelet (GNP) stabilizers. Subsequently, polymer-stabilized GNPs were formulated into film-forming polymer latex dispersions and the properties of the resulting GNP-containing films measured. Py-PMAA n homopolymers with well-defined molecular weights were prepared via RAFT solution polymerization. They served as efficient stabilizers for aqueous GNP dispersions and performed better than a traditional small molecule surfactant and non-functionalized PMAA, especially at higher pH and with higher molecular weight polymers. The use of Py-PMAA n allowed GNPs to be readily formulated into waterborne latex coatings. When compared to controls, the resulting films were significantly reinforced due to the improved homogeneity of dried nanocomposite films and chain entanglement between the polymer matrix and stabilizers. Thus, the ability to readily incorporate GNPs into aqueous formulations and enhance GNP/polymer matrix interfaces was demonstrated for these novel amphiphilic stabilizers. [ABSTRACT FROM AUTHOR]
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- 2024
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39. Simple-by-design approach for production of stabilizer-free cubosomes from phosphatidylglycerol and docosahexaenoic acid monoacylglycerol.
- Author
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Kalaycioglu, Gokce Dicle, Bor, Gizem, and Yaghmur, Anan
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DOCOSAHEXAENOIC acid , *LIQUID crystal states , *COLLOIDAL stability , *TRANSMISSION electron microscopy , *PHOSPHATIDYLGLYCEROL , *SMALL-angle X-ray scattering - Abstract
[Display omitted] Docosahexaenoic acid monoacylglycerol represents a promising lipid constituent in the development of drug nanocarriers owing to its amphiphilicity and the beneficial health effects of this docosahexaenoic acid precursor in various disorders including cancer and inflammatory diseases. Here, we describe the formation and characterization of simple-by-design and stabilizer-free lamellar and non-lamellar crystalline nanoparticles (vesicles and cubosomes, respectively) from binary mixtures of docosahexaenoic acid monoacylglycerol and phosphatidylglycerol, which is a ubiquitous amphiphilic component present in biological systems. At the physiological temperature of 37 °C, these single amphiphilic components tend to exhibit inverse hexagonal and lamellar liquid crystalline phases, respectively, on exposure to excess water. They can also be combined and dispersed in excess water by employing a high-energy emulsification method (by means of ultrasonication) to produce through an electrostatic stabilization mechanism colloidally stable nanodispersions. A colloidal transformation from vesicles to cubosomes was detected with increasing MAG-DHA content. Through use of synchrotron small-angle X-ray scattering, cryo-transmission electron microscopy, and nanoparticle tracking analysis, we report on the structural and morphological features, and size characteristics of these nanodispersions. Depending on the lipid composition, their internal liquid crystalline architectures were spanning from a lamellar (L α) phase to biphasic features of coexisting inverse bicontinuous (Q 2) cubic Pn3m and Im3m phases. Thus, a direct colloidal vesicle-cubosome transformation was detected by augmenting the concentration of docosahexaenoic acid monoacylglycerol. The produced cubosomes were thermally stable within the investigated temperature range of 5–60 °C. Collectively, our findings contribute to understanding of the imperative steps for production of stabilizer-free cubosomes from biocompatible lipids through a simple-by-design approach. We also discuss the potential therapeutic use and future implications for development of next-generation of multifunctional vesicles and cubosomes for co-delivery of docosahexaenoic acid and drugs in treatment of diseases. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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40. Enhancing colloidal stability of nanodiamond via surface modification with dendritic molecules for optical sensing in physiological environments.
- Author
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Głowacki, Maciej J., Niedziałkowski, Paweł, Ryl, Jacek, Prześniak-Welenc, Marta, Sawczak, Mirosław, Prusik, Klaudia, Ficek, Mateusz, Janik, Monika, Pyrchla, Krzysztof, Olewniczak, Michał, Bojarski, Krzysztof, Czub, Jacek, and Bogdanowicz, Robert
- Subjects
- *
X-ray photoelectron spectroscopy , *COLLOIDAL stability , *PHOTOELECTRON spectroscopy , *MOLECULAR dynamics , *DIAMOND surfaces - Abstract
[Display omitted] Pre-treatment of diamond surface in low-temperature plasma for oxygenation and in acids for carboxylation was hypothesized to promote the branching density of the hyperbranched glycidol polymer. This was expected to increase the homogeneity of the branching level and suppress interactions with proteins. As a result, composite nanodiamonds with reduced hydrodynamic diameters that are maintained in physiological environments were anticipated. Surfaces of 140-nm-sized nanodiamonds were functionalized with oxygen and carboxyl groups for grafting of hyperbranched dendritic polyglycerol via anionic ring-opening polymerization of glycidol. The modification was verified with Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. Dynamic light scattering investigated colloidal stability in pH-diverse (2–12) solutions, concentrated phosphate-buffered saline, and cell culture media. Thermogravimetric analysis of nanodiamonds-protein incubations examined non-specific binding. Fluorescence emission was tested across pH conditions. Molecular dynamics simulations modeled interparticle interactions in ionic solutions. The hyperbranched polyglycerol grafting increased colloidal stability of nanodiamonds across diverse pH, high ionic media like 10 × concentrated phosphate-buffered saline, and physiological media like serum and cell culture medium. The hyperbranched polyglycerol suppressed non-specific protein adsorption while maintaining intensive fluorescence of nanodiamonds regardless of pH. Molecular modelling indicated reduced interparticle interactions in ionic solutions correlating with the improved colloidal stability. [ABSTRACT FROM AUTHOR]
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- 2024
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- View/download PDF
41. Branched polymer grafted graphene oxide (GO) as a 2D template for calcium phosphate growth.
- Author
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Lee, Wai Hin and Bon, Stefan A.F.
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- *
BRANCHED polymers , *HOMOGENEOUS nucleation , *METHACRYLIC acid , *COLLOIDAL stability , *DIETHYLENE glycol - Abstract
[Display omitted] Graphene Oxide (GO)-templated deposition of inorganic materials through synthesis on dispersed single sheets of GO is often complicated by the loss of the desired 2D morphology owing to the coagulation of GO sheets at high salt concentrations and non-templated homogenous nucleation. Modifying GO with anionic polymer is expected to solve both problems by i) enhancing electrostatic(steric) stabilization upon exposure to high concentrations of the ionic precursors, and ii) offering additional nucleation sites at the grafted anionic moieties to avoid homogeneous secondary nucleation. GO was grafted with branched copolymers of poly(ethylene glycol) methacrylate (PEGMA 500) and diethylene glycol dimethacrylate (DEGDMA) and ω -vinyl terminated methacrylic acid macromonomer (P(MAA)), the latter serving as an addition-fragmentation chain transfer agent. The colloidal stability of GO dispersions in water toward salt was evaluated before and after modification. Precipitation of calcium phosphate (CaP) was performed by incubating modified GO in the precursor solutions. The conditions were optimized to maximize the nucleation selectively onto GO without homogeneous CaP nucleation and coagulation of the GO-sheets. The copolymer grafted GO-sheets shows superior colloidal stability when dispersed in water. No aggregation occurs in the incubating ionic CaP precursor solutions. The optimum templated deposition of CaP onto the GO sheets by precipitation is to add a second shot of precursors after the nucleation stage to obtain GO sheets fully decorated with calcium phosphate nanorods without self-nucleation. Via the careful design on the GO modification and incubation process, the growth of calcium phosphate nanorods were confined in the desired 2D order exclusively, hereby achieving the goal of an efficient GO-templated synthesis. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
- View/download PDF
42. Photoinduced electron transfer across the polymer-capped CsPbBr3 interface in a polar medium.
- Author
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Kipkorir, Anthony, Jin, Xiuyu, Gao, Haifeng, and Kamat, Prashant V.
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- *
PHOTOINDUCED electron transfer , *BINDING constant , *CHARGE exchange , *PHOTOREDUCTION , *ELECTROPHILES , *COLLOIDAL stability - Abstract
In-situ polymer capping of cesium lead bromide (CsPbBr3) nanocrystals with polymethyl acrylate is an effective approach to improve the colloidal stability in the polar medium and thus extends their use in photocatalysis. The photoinduced electron transfer properties of polymethyl acrylate (PMA)-capped CsPbBr3 nanocrystals have been probed using surface-bound viologen molecules with different alkyl chains as electron acceptors. The apparent association constant (Kapp) obtained for the binding of viologen molecules with PMA-capped CsPbBr3 was 2.3 × 107 M−1, which is an order of magnitude greater than that obtained with oleic acid/oleylamine-capped CsPbBr3. Although the length of the alkyl chain of the viologen molecule did not show any impact on the electron transfer rate constant, it influenced the charge separation efficiency and net electron transfer quantum yield. Viologen moieties with a shorter alkyl chain length exhibited a charge separation efficiency of 72% compared with 50% for the longer chain alkyl chain length viologens. Implications of polymer-capped CsPbBr3 perovskite nanocrystals for carrying out photocatalytic reduction in the polar medium are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
43. Enhanced chemotherapy response in hepatocellular carcinoma: synergistic effects of miR-122 and doxorubicin co-delivery system inducing apoptosis and DNA damage.
- Author
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Lin, Xiuyun, Liu, Jie, Wu, Guangfeng, Yang, Xiu, Yan, Wenqiang, Fan, Nanfeng, and Li, Hui
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- *
MICRORNA , *HEPATOCELLULAR carcinoma , *COLLOIDAL stability , *CELL death , *DNA damage , *DNA repair - Abstract
Background: Cancer cells can resist chemotherapy through various mechanisms, diminishing treatment outcomes. Research had indicated that combining miR-122 with doxorubicin (DOX) can improve hepatocellular carcinoma (HCC) therapy. Results: To explore this, we created a one-pot co-delivery system, Fe-miR-122/DOX, by coordinating miR-122, DOX, and FeII ions into nanoparticles. These nanoparticles display uniform particle sizes, well-defined morphology, and exceptional colloidal stability in 10% FBS and 20% FBS solution over 24 h. When the ratio of DOX to miR-122 was set at 20:1, the loading efficiency of both drugs reached 54.7% and 55.5%, respectively. Cell experiments confirmed that Fe-miR-122/DOX efficiently delivers both miR-122 and DOX, enabling cytoplasmic delivery through lysosomal escape, facilitated by the positive charge of the nanoparticles. Functionally, miR-122 increases intracellular accumulation of DOX by downregulating P-glycoprotein (P-gp) expression, and it promotes apoptosis by downregulating B-cell lymphoma 2 (Bcl-2), which leads to the upregulation of Caspase-3. Additionally, Fe-miR-122/DOX disrupts cIAPs-mediated anti-apoptotic signals, downregulates PARP-1 expression, hinders DNA repair, promotes DNA fragmentation, enhances caspase-3 expression, and triggers programmed cell death, synergistically enhancing its antitumor efficacy. This synergistic mechanism disrupts DNA repair, amplifying DNA damage and apoptosis. Our cytotoxicity and apoptosis assays (with a HepG2 cell apoptosis rate of 85.98%) demonstrated the potent antitumor capability of Fe-miR-122/DOX. Conclusions: This innovative system has demonstrated good biocompatibility and has the potential to transform HCC therapy. Future research could focus on optimizing the co-delivery system and assessing its efficacy in clinical trials. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
44. Efficient green light-emitting diodes based on alloy quantum dots with an organic/inorganic hybrid surface passivation.
- Author
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Chen, Zhao, Chen, Xiaohan, Zhang, Yan, Zhan, Yunfeng, Yuan, Guoqiang, Lu, Xianfei, Zhang, Wenxin, Li, Yang, Liu, Xi, and Meng, Fanyuan
- Subjects
- *
SURFACE passivation , *LIGHT emitting diodes , *QUANTUM dots , *X-ray photoelectron spectroscopy , *COLLOIDAL stability , *OLEIC acid - Abstract
As we know, the ligands on the surface of core/shell structured quantum dots (QDs) play an important role. They not only bind with metal ions to passivate surface defects but also have a great influence on colloidal stability. All-organic or all-inorganic ligands afford QDs with some disadvantages such as low conductivity, poor dispersibility and undesirable stability. By combining with the advantages of organic and inorganic ligands, herein, we achieve an organic/inorganic hybrid surface passivation through exchanging partial oleic acid ligands with chlorine ions (Cl−), affording QD with a core/shell structure of CdZnSe/ZnSe/ZnS/OACl. It exhibits an excellent nanostructure with a mean size of around 11.6 nm. According to X-ray photoelectron spectroscopy (XPS) spectra, around 30% oleid acid ligands are removed by Cl−, resulting in the hybrid surface passivation. The CdZnSe/ZnSe/ZnS/OACl QD exhibit an efficient green emission at the wavelength of around 535 nm with a quantum yield of over 90%. The QD light-emitting diode (QLED) based on CdZnSe/ZnSe/ZnS/OACl exhibits a peak EQE of 15.6% and a brightness of over 1.1 × 105 cd m−2 at 6 V, corresponding to an efficient green emitting device. Therefore, we believe that the hybrid surface passivation could provid a reliable avenue to efficient QD materials. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
45. Impact of Thermally Inactivated Non- Saccharomyces Yeast Derivatives on White Wine.
- Author
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Civa, Valentina, Maioli, Francesco, Canuti, Valentina, Pietrini, Bianca Maria, Bosaro, Matteo, Mannazzu, Ilaria, and Domizio, Paola
- Subjects
PROTEIN stability ,COLLOIDAL stability ,SACCHAROMYCES cerevisiae ,OXYGEN consumption ,POLYSACCHARIDES ,WHITE wines - Abstract
While a recent characterization of non-Saccharomyces thermally inactivated yeasts (TIYs) in a wine-like solution highlighted the release of oenologically relevant compounds and different oxygen consumption rates and antioxidant activity, here the impact of TIYs derived from Saccharomycodes ludwigii (SL), Metschnikowia pulcherrima (MP), Torulaspora delbrueckii (TD), and Saccharomyces cerevisiae (SC), as the reference strain, was evaluated in white wine. Wine treatment with TIYs resulted in an increase in polysaccharide concentration compared to the untreated wine, with SL-TIY exhibiting the highest release. Additionally, all TIYs, particularly SL-TIY, improved protein stability by reducing heat-induced haze formation. The addition of TIYs also demonstrated an effect on color parameters through phenolic compound adsorption, preventing potential browning phenomena. All TIYs significantly impacted the wine's volatile profile. Overall, it was shown that an improvement in wine quality and stability may be obtained by using TIYs in the winemaking process. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. Customizing Cerium Oxide Particle Synthesis with Hybrid Polyion Complex Templates for Enhanced Oxidation Performance in Photo‐Fenton Processes.
- Author
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Peng, Liming, Benoît‐Marquié, Florence, and Marty, Jean‐Daniel
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- *
METAL catalysts , *COLLOIDAL stability , *METHYLENE blue , *POLLUTANTS , *METALLIC oxides , *PRUSSIAN blue , *CERIUM oxides - Abstract
Hybrid poly‐ion complexes were synthesized through the complexation of a double hydrophilic copolymer with Ce(III) ions. These colloids act as reservoirs for cerium ions, enabling the synthesis of cerium‐based Prussian blue nanoparticles with a cubic structure, a narrow size distribution around 100 nm, and good colloidal stability in water. Upon high‐temperature calcination, these nanoparticles are transformed into a cerium/iron‐based metal oxide catalyst (CeO2/Fe2O3). The resultant composite catalyst demonstrates superior performance in the photo‐Fenton oxidation of methylene blue pollutants, achieving a conversion efficiency that rivals other metal‐based oxides and cerium‐based catalysts. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
47. Chitosan Nanoparticle-Mediated Delivery of Curcumin Suppresses Tumor Growth in Breast Cancer.
- Author
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Mishra, Barnalee, Yadav, Amit Singh, Malhotra, Diksha, Mitra, Tandrima, Sinsinwar, Simran, Radharani, N. N. V., Sahoo, Saroj Ranjan, Patnaik, Srinivas, and Kundu, Gopal C.
- Subjects
- *
BREAST cancer , *TUMOR growth , *COLLOIDAL stability , *CELL migration , *DRUG efficacy , *BREAST - Abstract
Curcumin is a nutraceutical known to have numerous medicinal effects including anticancer activity. However, due to its poor water solubility and bioavailability, the therapeutic impact of curcumin against cancer, including breast cancer, has been constrained. Encapsulating curcumin into chitosan nanoparticles (CHNPs) is an effective method to increase its bioavailability as well as antitumorigenic activity. In the current study, the effects of curcumin-encapsulated CHNPs (Cur-CHNPs) on cell migration, targeted homing and tumor growth were examined using in vitro and in vivo breast cancer models. Cur-CHNPs possessed a monodispersed nature with long-term colloidal stability, and demonstrated significant inhibition of cell viability in vitro, which was potentiated by 5-Fluorouracil (5-FU). Outcomes of the in vivo imaging studies confirmed effective tumor targeting and retention ability of Cur-CHNPs, thereby suppressing breast tumor growth in mice models. Overall, the results demonstrated that Cur-CHNPs could be an effective candidate drug formulation for management of breast cancer. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
48. Colloidal Stability of Chitosan/DNA Polyelectrolyte Complexes in Presence of Biological Polyanions.
- Author
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Nando Rodríguez, Jesrael Luz Elena, Figueroa Ochoa, Edgar Benjamín, Renteria Urquiza, Maite, and Bravo‐Anaya, Lourdes Mónica
- Subjects
- *
PHYSICAL & theoretical chemistry , *NUCLEIC acids , *POLYANIONS , *COLLOIDAL stability , *POLYELECTROLYTES , *GLYCOSAMINOGLYCANS - Abstract
Natural or synthetic polycations are used in nucleic acid‐based therapies as complexing agents which interact electrostatically with nucleic acids, condense them into nanoparticles, protect them and control their entry into cells. However, although the literature on the formation of nanoparticles known as complexes is well documented, fewer studies have focused on the physical chemistry behind their disassembly, especially under physicochemical conditions found in an intracellular environment. There are several theories of the disassembly of these complexes, one of them consisting in the exchange between the polycations of these particles with biological polyanions. This project is focused on the study of the complexation mechanism of chitosan and calf‐thymus DNA, as well as the stability of the obtained complexes in presence of biological polyanions, i.e., glycosaminoglycans (GAGs). In the presence of polyelectrolyte complexes, GAGs that are present in cells are expected to compete with nucleic acids and dissociate the complex if polycation–GAG association is thermodynamically favored. It is found that chitosan/DNA complexes colloidal stability depends on its [N+]/[P−] charge ratio (R). Furthermore, it is determined that the aggregation onset of the complexes, generated by the addition of different GAGs, depends on the structure and the charge density of the GAGs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. Biopolymer‐Based Nanogels Synthesis, Characterization, and Stability for Doxorubicin Encapsulation and Delivery.
- Author
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Fernández‐Solís, Karla Gricelda, González, Guillermo Toriz, Ochoa, Edgar Benjamín Figueroa, Rosselgong, Julien, Mijares, Eduardo Mendizabal, and Bravo‐Anaya, Lourdes Mónica
- Subjects
- *
COLLOIDAL stability , *NANOGELS , *ACTIVE biological transport , *MOLECULAR weights , *FUNCTIONAL groups - Abstract
Nanogels are nanostructures with dimensions within the nanoscale, composed of crosslinked polymers through their functional groups. Nanogels can display sensitiveness to stimuli, such as pH or temperature. This characteristic has been used in the design of new platforms for the transport and release of active ingredients. Biopolymer‐based nanogels are of great interest due to their biodegradability, biocompatibility, nontoxicity, and among others. In this project, pH‐responsive nanogels are synthesized through a novel methodology, using two polysaccharides classified as safe, biocompatible, and easily accessible materials, i.e., chitosan (CS) and maltodextrin (MD). A reductive amination reaction between CS and partially oxidized MDs allows to synthesized MD/CS nanogels with sizes ranging from 90 ± 5 to 194 ± 40 nm and with a colloidal stability up to 7 weeks. It is found that the variation of nanogels size and charge depends on CS concentration, molecular weight, and pH, as well as on the % oxidation of the MD. As evidence of nanogels pH‐responsiveness, an increase of size and ζ‐potential is observed by decreasing the pH. This size increase is attributed to the swelling of the nanogels upon a change in pH. Finally, doxorubicin is encapsulated in MD/CS nanogels, with a loading capacity up to 57%. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. The colloidal stability of water-in-oil-in-water double emulsion stabilized by Pickering emulsifier mixture in encapsulating ethanolic kenaf leaves extract.
- Author
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Elaine, Elaine, Tan, Chin Ping, Akanda, Md Jahurul Haque, and Nyam, Kar Lin
- Subjects
SODIUM caseinate ,FOOD emulsions ,COLLOIDAL stability ,KENAF ,MOLECULAR interactions - Abstract
Double emulsion (DE) has recently attracted attention due to its ability to encapsulate hydrophilic and hydrophobic substances and controlled release properties. However, food-grade DE is prone to destabilization due to its complex structure, which makes practical application in the industries difficult. This study investigates the stabilization of DE containing ethanolic kenaf leaf extract using different concentrations of Pickering emulsifier mixture (PEM). PEM consists of sodium caseinate, tween-20, and beta-cyclodextrin at the fixed ratio of 57.9:27.6:14.5% (w/w/w). Key parameters such as droplet size, polydispersity index, creaming index, encapsulation efficiency, and droplet morphology were monitored during 5-week storage at 25 °C. All DE samples remained phase-stable and exhibited increasing viscosity throughout the storage. The droplets displayed a spherical shape, and functional group assessment indicated changes in the molecular interactions after ultrasonic emulsification. DE stabilized by 2.5% and 4.0% (w/w) PEM consistently maintained droplet size and distribution, achieving encapsulation efficiency exceeding 98%. Specifically, DE with 4.0% (w/w) PEM exhibited excellent resistance to pH changes. In conclusion, PEM-stabilized DE remained stable for up to 5 weeks at 25 °C, which facilitates the beneficial uses of double emulsion in food, cosmetic, and medical applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
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