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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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

The enormous therapeutic potential of selective ribonucleic acid (RNA) interference has recently been manifested by the approval of several small interfering RNA (siRNA)‐based drugs. However, the efficacy of siRNA delivery is still limited, and an extensive search for alternative and highly effective delivery approaches is ongoing. With this aim, three generations of non‐viral vectors based on modified nanodiamonds (NDs) have been gradually developed in the past decade. They show great promise due to the negligible toxicity of the ND core. Here, a robust methodological approach is presented to enable the evaluation of new vector nanomaterials. Using a new type of third‐generation ND vector coated with a copolymer with tunable charge density, variables such as colloidal stability, surface electrostatic properties, the molecular composition of the copolymer, and the mode of complexation with siRNA are optimized. Using an innovative data processing strategy, the results are related to biological potency, toxicity, and cell proliferation. Finally, the optimized composition of a coating copolymer consisting of a cationic component, 2‐dimethylaminoethyl methacrylate, and an electroneutral biocompatible component, N‐(2‐hydroxypropyl) methacrylamide, is evaluated. The optimized NDs vectors are colloidally and biologically stable siRNA delivery tools with broad potential for RNA interference‐based therapeutics. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Reversible addition‐fragmentation chain transfer (RAFT)‐mediated polymerization‐induced self‐assembly (PISA) of star block copolymer and linear block copolymer using a binary mixture of a star‐like macro‐RAFT agent and a linear macro‐RAFT agent is reported. With this formulation, star block copolymer and diblock copolymer were formed simultaneously to generate colloidally stable star/linear block copolymer assemblies. Size exclusion chromatography (SEC) analysis confirmed the presence of two types of polymers in the final samples. The molar ratio of the star‐like macro‐RAFT agent and the linear macro‐RAFT agent has a significant impact on the morphology of polymer assemblies. It was found that increasing the amount of star‐like macro‐RAFT agent facilitated the formation of higher‐order morphologies. Additionally, effects of other reaction parameters including the length/number of the arm of the star‐like macro‐RAFT agent, degree of polymer (DP), monomer concentration on the morphology of star/linear block copolymer assemblies were also investigated. We expect that this work will offer new possibilities for the scalable preparation of polymer assemblies with unique structures and functions. [ABSTRACT FROM AUTHOR]

Encapsulation of bioactive molecules for therapeutic use is gaining great interest in the scientific community. Several encapsulation methodologies have been evaluated, sacrificing, in some cases, either encapsulation efficiency or compound integrity. Our work developed Maillard conjugates (MCs) based on the whey protein (WP)‐Maltodextrin (MD) interaction to encapsulate quercetin by freeze‐drying. The WP:MD ratio used (1:2 or 1:3) yielded the formation of MCs, demonstrated by an increased browning index and changes in the protein secondary structure. Freeze‐drying showed high encapsulation efficiency, reaching 87.65% and 84.72% in treatments loaded with 3.3 mg quercetin/g MCs. Quercetin‐loaded MCs showed spherical‐shape (4–10 μm) and a negative charge, suggesting colloidal stability. Moreover, in vitro tests demonstrated a sustained release of quercetin throughout the oral, gastric, and intestinal phases, highlighting the MCs efficacy as bioactive delivery systems. This work provides useful information to design bioactive compound delivery systems for food and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

We report on the preparation of a polyethyleneimine‐incorporated hydroxyapatite (PEI‐HAP) and its enhanced colloidal stability. Three PEI‐HAPs having different amine contents are synthesized by hydrothermal treatment (200 °C) of the HAP prepared at room temperature (rt‐HAP). The crystallinity of PEI‐HAP is improved compared to rt‐HAP due to the heat treatment. In addition, the size of PEI‐HAP (50.4 nm) increased compared to rt‐HAP (32.1 nm) after heat treatment. However, the presence (or concentration) of PEI has little effect on the crystallinity and size of the samples. Ninhydrin test indicates the presence of amine group in PEI‐HAPs. XPS experiments verified that maximum amine content amounts to 2.81%. As the amount of amine increases, the zeta potential is changed from −22.6 to +31.7 mV due to the adsorption of PEI on HAP surface. Consequently, the sample having high positive valuable zeta potential of +31.7 mV exhibits colloidal stability of more than 6 h. [ABSTRACT FROM AUTHOR]

We present a straightforward one‐pot hydrothermal method for the synthesis of zirconia nanodispersions, leading to the formation of stable sols. By simply varying the nature of the stabilizer used, one can obtain a large variety of objects with different sizes, shapes and crystallinities. Our results demonstrate the crucial role played by aliphatic amino acids both during the formation of the objects and after, since their interaction with the surface of the inorganic crystals influences strongly the optical properties and colloidal stability of the latter. Importantly, the versatility of this method allows for the introduction of different dopants, increasing substantially the scope of applications that can be achieved with such nanoscale oxides. The high transparencies and the easy dispersibility of nanoparticles in different liquid matrixes ensure the formation of zirconia‐based nanocomposites and ceramics with outstanding optical features for the orthopedic, dental, photonics and chemical sectors. This method can be easily scaled up, being already available for the production of high‐quality zirconia nanodispersions at the industrial level. [ABSTRACT FROM AUTHOR]

In semiconductor‐metal hybrid nanoparticles, excited charge carriers can be separated efficiently by transferring the electron to the metal, because the Fermi level is located within the bandgap of the semiconductor. Besides charge carrier separation, the catalytically active surface of the metal enables the use of these charge carriers for further reactions. Due to limited colloidal stability, the application of nanoparticles in solution is challenging. To circumvent these difficulties, the destabilization can be used to build monolithic 3D (non‐ordered) gel‐like structures with retained high surface area and an ensured diffusion within the network. Here, the resulting nanoparticle‐based hydrogels of CdSe/CdS/Pt nanoparticles show photocatalytic hydrogen production rates up to 58 (mmol(H2))/(g∙h). Due to the self‐supporting network structure, colloidal stability is unnecessary, and the applicability is improved. By simply mixing semiconductor and semiconductor–metal hybrid nanoparticles before gelation, the synthesis of the gels allows the reduction of the metal content, which further tunes the photocatalyst. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have gained remarkable attention as therapeutic agents since the appearance of nanotechnology. This study aims to assess the protective impact of chitosan‐silver nanoparticles (CS‐AgNPs) against DEN‐induced hepatocellular injury by regulation of Wnt/β‐Catenin and apoptosis signaling pathways in rats. CS‐AgNPs solutions were prepared by mixing different concentrations of chitosan and silver nitrate, and then subjected to gamma radiation at 20 kGy. The formation of CS‐AgNPs could be observed by naked eyes from the colour change from light yellow to reddish‐brown, and confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Stability measurements confirmed that the prepared Cs‐AgNPs are highly stable for around 8 weeks. A crystal violet cytotoxicity assay of CS‐AgNPs has been detected in vitro on HepG2 hepatocellular carcinoma cell lines. The obtained results confirmed the selective influence of CS‐AgNPs on the HCC cell line in a time and dose dependent manner. Diethylnitrosamine (DEN) induced a marked increase in the expressions of Wnt, β‐Catenin, STAT3, MMP9, and Bcl‐2 with a significant decrease in the expression of BAX, p53, and P21. Additionally, DEN significantly decreased the levels of Cytc and TPTH while significantly increased the levels of COX‐2, PGE2, TGF‐1, AFP, and liver enzyme activity. The role of CS‐AgNPs is documented in diminishing the expressions of Wnt, β‐Catenin, STAT3, MMP9, and Bcl‐2. Also, CS‐AgNPs induced the decrease in the levels of COX‐2, PGE2, TGF‐1, AFP and liver enzyme activity accompanied by increased apoptosis. These results concluded that CS‐AgNPs might be a promising drug designed for treating liver diseases. [ABSTRACT FROM AUTHOR]

Smart nanoassemblies degradable through the cleavage of acid‐labile linkages have attracted significant attention because of their biological relevance found in tumor tissues. Despite their high potential to achieve controlled/enhanced drug release, a systematic understanding of structural factors that affect their pH sensitivity remains challenging, particulary in the consruction of effective acid‐degradable shell‐sheddable nanoassemblies. Herein, the authors report the synthesis and acid‐responsive degradation through acid‐catalyzed hydrolysis of three acetal and ketal diols and identify benzaldehyde acetal (BzAA) exhibiting optimal hydrolysis profiles in targeted pH ranges to be a suitable candidate for junction acid‐labile linkage. The authors explore the synthesis and aqueous micellization of well‐defined poly(ethylene glycol)‐based block copolymer bearing BzAA linkage covalently attached to a polymethacrylate block for the formation of colloidally‐stable nanoassemblies with BzAA groups at core/corona interfaces. Promisingly, the investigation on acid‐catalyzed hydrolysis and disassembly shows that the formed nanoassemblies meet the criteria for acid‐degradable shell‐sheddable nanoassemblies: slow degradation at tumoral pH = 6.5 and rapid disassembly at endo/lysosomal pH = 5.0, while colloidal stability at physiological pH = 7.4. This work guides the design principle of acid‐degradable shell‐sheddable nanoassemblies bearing BzAA at interfaces, thus offering the promise to address the PEG dilemma and improve endocytosis in tumor‐targeting drug delivery. [ABSTRACT FROM AUTHOR]

Summary: Psyllium husk has attracted increasing interest in food applications due to its well‐known health benefits. Size reduction is an important mechanical operation used to tailor the functional properties of materials. In this study, the physicochemical properties and colloidal stability of the PHPs with different sizes were characterised by particle size distribution, zeta potential, Fourier transform infrared (FT‐IR) and X‐ray photoelectron spectroscopy (XPS). Furthermore, the size effects of psyllium husk on surimi gel properties were investigated in terms of the gel strength, water‐holding capacity (WHC) and water distribution. The results found that milling changed the monosaccharide composition and increased the diffraction intensity of psyllium husk powder (PHP) without disrupting the β‐glycosidic linkages. Furthermore, the XPS results suggested that smaller samples showed more exposed surface functional groups. The PHP3 group with average size of d (0.5) = 259.50 μm exhibited the highest absolute zeta potential. The viscosity and zeta potential of PHP correlated positively and negatively with the gel strength of surimi, respectively. Moreover, the micronized PHP also contributed to the increase in immobilised water content and uniform water distribution in surimi gels. The high viscosity and colloidal stability of psyllium husk (PHP3 group) contributed to the improved mechanical properties of surimi gels. This work provides a valuable reference for the potential use of psyllium husk in quality improvement of surimi products through size control. [ABSTRACT FROM AUTHOR]

The efficiency and lifetime of inkjet‐printed QD‐LED displays are improved through the ligand exchange of Cd‐free QDs and optimal control of ink formulation. Dual ligands enhance colloidal stability and carrier transport properties. The introduction of appropriate additives in the mixed solvent system improves the inkjet processibility and the morphology of inkjet printed layers. [ABSTRACT FROM AUTHOR]

Polymer‐coated nanoparticles are widely studied in the context of nanomedicine and it is therefore of utmost importance to understand not only how their structure but also how their colloidal dynamics are affected by physiologically relevant conditions. A characteristic feature of the cytosol of cells is the very high concentration of proteins among other matrix components, often termed macromolecular crowding. Here, the structure and colloidal dynamics of poly(ethylene glycol) (PEG)‐coated gold nanoparticles in the presence of bovine serum albumin (BSA) concentrations ranging from 0 to 265 mg/mL are studied with X‐ray photon correlation spectroscopy. For protein–nanoparticle mixtures with high BSA concentrations, comparable to intracellular levels, a significant deviation of the apparent viscosity from expectations for pure BSA solutions is found. The findings strongly indicate that the nanoscopic viscous properties of the dense protein solutions are significantly affected by the nanoparticles. At these high concentrations, the colloidal stability of the samples depends on the molecular weight of the coating PEG–ligand, whereas at lower concentrations no differences are observed. [ABSTRACT FROM AUTHOR]

Surface enhanced resonance Raman (SERS) is a powerful optical technique, which can help enhance the sensitivity of Raman spectroscopy aided by noble metal nanoparticles (NPs). However, current SERS‐NPs are often suboptimal, which can aggregate under physiological conditions with much reduced SERS enhancement. Herein, a robust one‐pot method has been developed to synthesize SERS‐NPs with more uniform core diameters of 50 nm, which is applicable to both non‐resonant and resonant Raman dyes. The resulting SERS‐NPs are colloidally stable and bright, enabling NP detection with low‐femtomolar sensitivity. An algorithm has been established, which can accurately unmix multiple types of SERS‐NPs enabling potential multiplex detection. Furthermore, a new liposome‐based approach has been developed to install a targeting carbohydrate ligand, i.e., hyaluronan, onto the SERS‐NPs bestowing significantly enhanced binding affinity to its biological receptor CD44 overexpressed on tumor cell surface. The liposomal hyaluronan (HA)‐SERS‐NPs enabled visualization of spontaneously developed breast cancer in mice in real time guiding complete surgical removal of the tumor, highlighting the translational potential of these new glyco‐SERS‐NPs. [ABSTRACT FROM AUTHOR]

Quantum dot light‐emitting diodes (QD‐LEDs) have received significant attention as a next‐generation display technology aimed at large‐size panel production with lower manufacturing costs and excellent picture quality. Here, we demonstrated all‐inkjet‐printed 12.4‐in. full‐color QD‐LED display with the 182‐ppi resolution. The efficiency and lifetime of inkjet‐printed QD‐LEDs were improved through the ligand exchange of Cd‐free quantum dots (QDs), red and green InP and blue ZnSeTe QDs, and optimal control of ink formulation. Dual ligands enhanced colloidal stability and carrier transport properties. The introduction of appropriate additives in the mixed solvent system improved the inkjet processibility and the morphology of inkjet‐printed layers. [ABSTRACT FROM AUTHOR]

In this work, a highly efficient photosensitive quantum dot (QD) system was designed. The optimized photosensitive QD system had high photoluminescence quantum yield and colloidal stability. By direct photolithography, RGB pixel arrays with a single sub‐pixel size of 39 μm × 5 μm were successfully prepared. Further, the full‐color QLED device was realized. There were no residual QD emission peaks from neighboring sub‐pixels observed in the electroluminescence spectra. Experience on the full‐color QLED device guided the successful preparation of a 4.7‐inch 650 PPI active matrix QLED prototype. The active matrix QLED prototype could display clear and complete pictures. The color gamut reached 85% of the BT2020 standard. This is the first active matrix QLED prototype prepared with a record‐high resolution by direct photolithography, which promoted the development of QLED display technology. [ABSTRACT FROM AUTHOR]

Aptamers are widely used in biosensing due to their specific sensitivity toward many targets. Thus, gold nanoparticle (AuNP) aptasensors are subject to intense research due to the complementary properties of aptamers as sensing elements and AuNPs as transducers. We present herein a novel method for the functional coupling of thrombin‐specific aptamers to AuNPs via an anionic, redox‐active poly(ferrocenylsilane) (PFS) polyelectroyte. The polymer acts as a co‐reductant and stabilizer for the AuNPs, provides grafting sites for the aptamer, and can be used as a redox sensing element, making the aptamer‐PFS‐AuNP composite (aptamer‐AuNP) a promising model system for future multifunctional sensors. The aptamer‐AuNPs exhibit excellent colloidal stability in high ionic strength environments owing to the combined electrosteric stabilizing effects of the aptamer and the PFS. The synthesis of each assembly element is described, and the colloidal stability and redox responsiveness are studied. As an example to illustrate applications, we present results for thrombin sensitivity and specificity using the specific aptamer. [ABSTRACT FROM AUTHOR]

Aptamers are widely used in biosensing due to their specific sensitivity toward many targets. Thus, gold nanoparticle (AuNP) aptasensors are subject to intense research due to the complementary properties of aptamers as sensing elements and AuNPs as transducers. We present herein a novel method for the functional coupling of thrombin‐specific aptamers to AuNPs via an anionic, redox‐active poly(ferrocenylsilane) (PFS) polyelectroyte. The polymer acts as a co‐reductant and stabilizer for the AuNPs, provides grafting sites for the aptamer, and can be used as a redox sensing element, making the aptamer‐PFS‐AuNP composite (aptamer‐AuNP) a promising model system for future multifunctional sensors. The aptamer‐AuNPs exhibit excellent colloidal stability in high ionic strength environments owing to the combined electrosteric stabilizing effects of the aptamer and the PFS. The synthesis of each assembly element is described, and the colloidal stability and redox responsiveness are studied. As an example to illustrate applications, we present results for thrombin sensitivity and specificity using the specific aptamer. [ABSTRACT FROM AUTHOR]

The size of acrylamide‐based microgels can be decreased by addition of ionic surfactants during the classical dispersion polymerization. Nevertheless, the mechanism of such syntheses is not well understood yet. Here, a "Limited Aggregation Model" is proposed by analogy with the limited coalescence mechanism occurring for Pickering emulsion stabilization. In such a model, nuclei aggregate until a constant, high enough surfactant surface coverage is reached, which ensures colloidal stability. Consequently, the total surface of the growing particles, linked to the inverse of their size, is linearly dependent on the surfactant concentration. This law is verified if the surfactant/polymer particle interaction is high enough to guarantee a "total adsorption" of the surfactants onto the particles. This simple model fits very well with all the data extracted from the literature, including very different synthesis conditions. Finally, it not only permits to predict the microgels size, but it is also an interesting tool to investigate the role of each synthesis parameter like initiator, solvent or polymer. For instance, it shows that the surfactant role is not linked to its charge, proving that a phenomenon complementary to the electrostatic repulsion, related to the surfactant tail, ensures the colloidal stability of the growing collapsed microgels. [ABSTRACT FROM AUTHOR]

Polyethylene glycol (PEG) exhibits poor residence on mucosal membranes in the presence of biological fluid, and the influence of PEG boronation on its properties has never been investigated. This project aimed to synthesise boronated 4‐arm PEG and evaluate their pH stability, thermal properties and mucoadhesiveness for potential transmucosal applications. Two types of boronated 4‐armed PEG (B4PEG1 & B4PEG2) and a boronated linear PEG (BLPEG) were synthesized. The degree of boronation, mucoadhesiveness, thermal and pH stability of the polymers were assessed using 1H NMR spectroscopy, viscometry, thermogravimetric analysis and UV–visible spectroscopy, respectively. Gel Permeation Chromatography was employed to confirm PEG boronation. The respective degrees of boronation for B4PEG1 and B4PEG2 were 32.8 % and 46.2 %. The molecular architecture and degree of PEG boronation had a remarkable influence on mucoadhesiveness, pH, and thermal stability. B4PEG2, with a branched architecture and the greatest degree of boronation, exhibited superior mucoadhesiveness and colloidal stability at pH 4 to 8, relative to B4PEG1 and BLPEG. Boronation improved the thermal stability of 4‐arm PEG. This study is the first to demonstrate that PEG boronation could enhance the pH‐sensitivity, thermal stability and mucoadhesiveness of 4‐arm PEG. Boronated 4‐arm PEGs could serve as mucoadhesive polymeric excipients for transmucosal drug delivery. [ABSTRACT FROM AUTHOR]

Poly(tertiary amine‐oxide)‐based polymeric nanocarriers have showed more functionalities than stealthy PEG‐based analogs due to the structure of phospholipid affinitive N‐oxides groups, which has attracted considerable attention to the synthesis of various zwitterionic copolymers with tertiary amine‐oxide grafts for enhanced anticancer drug delivery. However, poly(tertiary amine‐oxide)‐based amphiphilic copolymers with tumor intracellular microenvironment sensitivities, to the knowledge, have been rarely reported likely due to the lack of a controlled synthetic strategy. Herein, a reducible zwitterionic copolymer, poly(ε‐caprolactone)25‐SS‐poly(2‐(N‐oxide‐N,N‐diethylamino)ethyl methacrylate)30 (PCL25‐SS‐OPDEA30) is designed and synthesized successfully via combination of controlled polymerization techniques and post polymerization modification. Specifically, postoxidation of poly(tertiary amine) is confirmed to be a better synthetic strategy toward a well‐defined polymer structure relative to direct polymerization of N,N‐diethylaminoethyl methacrylate (ODEA). The effect of disulfide bridges on the self‐assembly behaviors, in vitro drug loading and drug release properties is investigated in detail. Notablely, the resulting micelles self‐assembled from PCL25‐SS‐OPDEA30 show much greater colloidal stability, higher drug loading content (DLC), and better in vitro tumor cell inhibition than the reduction‐insensitive counterparts. Overall, this study reports a robust strategy toward zwitterionic nanomedicines for on‐demand anticancer drug delivery. [ABSTRACT FROM AUTHOR]

A stable suspension of nanoparticles is generally achieved by modifying the surface properties of the nanoparticles using a surfactant. This is to create a surface charge on the nanoparticles which prevents them from forming aggregates. This phenomenon is very sensitive to changes in the local environment. Conventional optical tweezers though capable of trapping sub‐micrometer particles are not known to trap single nanoparticles. However, the stability and dynamics of a suspension of nanoparticles can be probed through the changes in the fluctuations of an optically trapped microsphere that has been added to the suspension. Adding microspheres to the nanoparticle suspension can affect the stability depending on the surface charges the microparticles themselves have. The study reports here on the variation of the dynamics of suspended nanoparticles, which have a positive surface charge, when silica microspheres, which are negatively surface charged, are added to the suspension. With the addition of silica beads, there is agglomeration of the nanoparticles. The dynamics of these agglomerated structures are then probed by measuring the Brownian fluctuations of an optically trapped silica bead. These results are in sharp contrast to those of earlier studies carried out with suspensions of identical nanoparticles but with negative surface charge. [ABSTRACT FROM AUTHOR]

The paper presents the colloidal and thermal stability of the three‐component hybrid materials containing halloysite, polysaccharides (alginic acid, cationic cellulose and hydroxyethyl cellulose) and Tritons. TX‐100, TX‐165 and TX‐405 were used as non‐ionic surfactants. Stability and other properties of the hybrid materials were tested by the following methods: UV–Vis, TGA (thermogravimetric analysis) and DSC (differential scanning calorimetry), CHN (elemental analysis), SEM‐EDX (scanning electron microscopy with energy dispersive X‐ray spectroscopy) and tensiometry. According to the results with the increasing polymer concentration the colloidal stability of the tested systems also increases. Moreover, the addition of the surfactants causes the increase of polysaccharide adsorption but the colloidal stability of the tested systems decreases due to large weights of formed aggregates. As follows from the thermal analysis, the comparison of the TG/DTG‐DSC curves obtained for the investigated polymers confirms that their thermal decomposition courses have some common features. The obtained results have the application potential in the formation of the materials for the pollutants removal from water and sewages. [ABSTRACT FROM AUTHOR]

Nowadays the use of hydrogels for biomedical purposes is increasing because of their interesting features that allow the development of targeted drug delivery systems. Herein, hydrogel based on Laponite® (Lap) clay mineral as gelator and cucurbit[6]uril (CB[6]) molecules were synthetized for the delivery of flufenamic acid (FFA) for potential topical application. Firstly, the interaction between CB[6] and FFA was assessed by UV‐vis spectroscopic measurements and molecular modeling calculations. Then, the obtained complex was used as filler for Lap hydrogel (Lap/CB[6]/FFA). The properties of the hydrogel in terms of viscosity and, self‐repair abilities were investigated; its morphology was imaged by scanning electron and polarized optical microscopies. Furthermore, the changes in the hydrodynamic radii and in the colloidal stability of CB[6]/Lap mixture were investigated in terms of translational diffusion from dynamic light scattering and ζ‐potential measurements. Finally, the kinetic in vitro release of FFA, from Lap/CB[6]/FFA hydrogel, was studied in a medium mimicking the pH of skin and the obtained results were discussed both by an experimental point of view and by molecular modeling calculations. [ABSTRACT FROM AUTHOR]

MXenes are electrically conductive 2D transition metal carbides/nitrides obtained by the etching of nanolaminated MAX phase compounds, followed by exfoliation to single‐ or few‐layered nanosheets. The mainstream chemical etching processes have evolved from pure hydrofluoric acid (HF) etching into the innovative "minimally intensive layer delamination" (MILD) route. Despite their current popularity and remarkable application potential, the scalability of MILD‐produced MXenes remains unproven, excluding MXenes from industrial applications. This work proposes a "next‐generation MILD" (NGMILD) synthesis protocol for phase‐pure, colloidally stable MXenes that withstand long periods of dry storage. NGMILD incorporates the synergistic effects of a secondary salt, a richer lithium (Li) environment, and iterative alcohol‐based washing to achieve high‐purity MXenes, while improving etching efficiency, intercalation, and shelf life. Moreover, NGMILD comprises a sulfuric acid (H2SO4) post‐treatment for the selective removal of the Li3AlF6 impurity that commonly persists in MILD‐produced MXenes. This work demonstrates the upscaled NGMILD synthesis of (50 g) phase‐pure Ti3C2Tz MXene clays with high extraction yields (>22%) of supernatant dispersions. Finally, NGMILD‐produced MXene clays dry‐stored for six months under ambient conditions experience minimal degradation, while retaining excellent redispersibility. Overall, the NGMILD protocol is a leap forward toward the industrial production of MXenes and their subsequent market deployment. [ABSTRACT FROM AUTHOR]

Terpenoids play a major role in agriculture, given their fungicidal and herbicidal actions, as well as their favorable toxicological, ecotoxicological, and environmental profiles. Despite all these advantages, terpenoids are reported to be unstable in direct sunlight and atmospheric conditions, so both commercial suppliers and scientific literature foresee their protection by encapsulation. The so‐called microcapsules (μCaps) are therefore of high relevance as drug‐delivery vectors, but very few techniques focus on their surface as well as on their morphological characterization. Indeed, these aspects are of great importance, given that their surface chemistry governs both their colloidal stability and mechanism of action. Common analysis techniques, such as chromatographic and mass‐spectrometric ones, are destructive, require sample preparation, and do not result in the complete morphological characterization of the microcapsules. Micro‐Raman spectroscopy, in conjunction with the surface‐enhanced Raman spectroscopy (SERS) effect, offers a valuable alternative method of investigation capable of achieving a complete and non‐destructive morphological characterization of the terpenoid‐encapsulating systems, the dimensions of which fall within the micrometric range. In addition, the SERS effect can be exploited by fabricating the microcapsules with gold nanostars (AuNSs) modified with chitosan and a SERS reporter (Nile Blue A). Thanks to the high contrast provided by the SERS signals of this tag, it was possible to localize and confirm the chitosan in the morphology of the microcapsules. The results of this study shed new light on the possibility of analyzing terpenoid‐encapsulating microcapsules and possibly other kinds of encapsulates brought by using Raman spectroscopy and by exploiting the SERS effect. [ABSTRACT FROM AUTHOR]

Background: Collagen is a major component of the extracellular matrix that supports the epidermal layers of the skin; thus, many strategies have been made to enhance the topical delivery of collagen for antiaging purposes. In addition, our previous study indicated that liposome can help the penetration of active ingredients into the skin. Aims: To produce stable collagen‐encapsulated liposomes to improve the topical delivery of collagen. Methods: Collagen‐encapsulated liposomes were fabricated using high‐pressure homogenization method. The colloidal stability and adhesion ability were confirmed using dynamic light scattering, and spectrofluorophotometer, respectively. Keratinocyte differentiations of 3D skin before and after treatment with collagen‐encapsulated liposomes were confirmed by real‐time PCR. Results: In comparison with native collagen, collagen‐encapsulated liposomes enhanced collagen retention in artificial membranes by twofold, even after repeated washings with water. In addition, real‐time PCR results indicated that 3D skin treated with collagen‐encapsulated liposomes exhibited higher levels of collagen, keratin, and involucrin, even after ethanol treatment. Conclusion: Liposomes could serve as efficient delivery vehicles for collagen, thereby enhancing its antiaging effects. [ABSTRACT FROM AUTHOR]

Carbon fiber (CF) reinforced polyether‐ether‐ketone (PEEK) composite is found extensive application in various industries. Efforts have been made to enhance the interfacial binding between the resin and fibers. Herein, we report a green CF surface modification suspension coating method that could resist high process temperature by optimizing the stability of the aqueous suspension, which contains PEEK resin particles and a mixture of sodium dodecyl sulfate (SDS) and polyethylene glycol monostearate (stPEG). The optimized suspension (PEEK: SDS mass ratio= 5:1) that can meet around 500°C process requirement was then used to improve the physical interfacial binding between CF and PEEK. Based on the suspension colloidal stability, the process was optimized by tensile tests of the CF/PEEK monofilaments. The results show that the colloidal stability of the PEEK aqueous suspension with a total solid content of 20 wt.% containing stPEG‐SDS (stPEG: SDS mass ratio= 1:2) surfactant blend (PEEK: stPEG‐SDS mass ratio= 5:1) reached the optimum at a stirring rate of 750 rpm. The maximum tensile strength of the CF/PEEK monofilaments reached ~4.968 GPa at a coating diameter of 8.54 μm. This PEEK aqueous suspension provides a non‐toxic, environmentally friendly and high temperature resistant aqueous material to produce high‐performance fiber reinforced PEEK composites. [ABSTRACT FROM AUTHOR]

Summary: Soy protein‐gum Arabic (GA) core‐shell nanoparticles were fabricated as carriers for hydrophobic phytosterol (PS) using an anti‐solvent precipitation (pH 7.0) and then coating GA on the surface of protein‐based PS nanoparticles at pH 4.5. PS nanoparticles stabilised by heat‐treated soy protein isolate (SPI), especially subcritical water‐treated SPI (SW, 120 °C), exhibited higher encapsulation efficiency (EE), loading amount (LA) and colloidal stability than native SPI‐stabilised PS nanoparticles. The highly flexible conformation and more exposed hydrophobic clusters of SW‐treated SPI could result in a quick encapsulation of more PS into the interior of protein molecules during anti‐solvent precipitation. However, for native SPI with rigid globular structure, the loading of PS mainly occurred on the surface hydrophobic sites of protein molecules. After introducing GA (≥5 mg mL−1) to PS nanoparticles fabricated by SW‐treated SPI, submicron‐sized (Dh 250.71~341.76 nm) core‐shell nanoparticles with high acid solubility and thermal stability were formed. The coating of GA decelerated the digestion of SW‐treated SPI, and improved the EE, LA and in vitro bioaccessibility of PS under acidic environment. These results reveal the protein structure dependence of PS encapsulation and provide a simple approach to fabricate biopolymer‐based nanoparticle delivery system for hydrophobic bioactives in acidified functional drinks. [ABSTRACT FROM AUTHOR]

Multifunctional biomaterial inks are in high demand for adapting hydrogels in biomedical applications through three‐dimensional (3D) printing. Our previously developed xeno‐free system consisting of anionic cellulose nanofibers (T‐CNF) and methacrylated galactoglucomannan (GGMMA) as a photo(bio)polymer provides high‐performance ink fidelity in extrusion‐based 3D printing. The fusion between nanoparticles and this biomaterial‐ink system is a promising yet challenging avenue worth exploring, due to the colloidal stability of T‐CNF being sensitive to electrostatic interactions. Mesoporous silica nanoparticles (MSNs), with their robust ceramic matrix and fine‐tunable surface chemistries, are well‐established nanocarriers for different biologicals. Here, we fabricated MSNs with different surface modifications resulting in a net surface charge ranging from highly negative to highly positive to develop printable MSNs‐laden nanocomposite biomaterial inks. We utilized rheology as a comprehensive tool to address the matrix interactions with differently surface‐charged MSNs. Fluorescently labeled bovine serum albumin (FITC‐BSA) was used as a model protein for MSN loading, whereby negatively or neutral‐charged MSNs were found suitable to formulate FITC‐BSA‐loaded biomaterial inks of T‐CNF/GGMMA. Depending on the particles' surface charge, FITC‐BSA showed different release profiles and preserved its stability after release. Lastly, the proof‐of‐concept to deliver large‐sized biological cargo with MSN‐laden nanocomposite biomaterial inks was established via the 3D printing technique. [ABSTRACT FROM AUTHOR]

Image contrast is often limited by background autofluorescence in steady‐state bioimaging microscopy. Upconversion bioimaging can overcome this by shifting the emission lifetime and wavelength beyond the autofluorescence window. Here we demonstrate the first example of triplet‐triplet annihilation upconversion (TTA‐UC) based lifetime imaging microscopy. A new class of ultra‐small nanoparticle (NP) probes based on TTA‐UC chromophores encapsulated in an organic–inorganic host has been synthesised. The NPs exhibit bright UC emission (400–500 nm) in aerated aqueous media with a UC lifetime of ≈1 μs, excellent colloidal stability and little cytotoxicity. Proof‐of‐concept demonstration of TTA‐UC lifetime imaging using these NPs shows that the long‐lived anti‐Stokes emission is easily discriminable from typical autofluorescence. Moreover, fluctuations in the UC lifetime can be used to map local oxygen diffusion across the subcellular structure. Our TTA‐UC NPs are highly promising stains for lifetime imaging microscopy, affording excellent image contrast and potential for oxygen mapping that is ripe for further exploitation. [ABSTRACT FROM AUTHOR]

Three‐photon fluorescence (3PF) imaging excited at 1700 nm window is an enabling technology for visualizing deep brain structures and dynamics. Recently, the 2200 nm window has emerged as the longest excitation window suitable for deep‐brain 3PF imaging. Bright fluorescent probes lay the material basis for deep‐brain 3PF imaging. Among various fluorescent probes, aggregation‐induced emission luminogens (AIEgens) have great potential in 3PF imaging excited at the 1700 nm window in vivo. However, to the best of knowledge, there is no AIEgens applicable to 3PF imaging excited at both the 1700 and 2200 nm windows. To readily fill this gap, here this study designs and synthesizes a novel AIEgen, namely TPE‐DPTT‐ICP, which generates bright 3PF signals excited at both 1700 and 2200 nm. The accordingly fabricated TPE‐DPTT‐ICP nanoparticles (NPs) possess excellent water dispersibility, colloidal stability, biocompatibility, photostability and large 3P action cross section, key to in vivo imaging. In mouse brain in vivo, TPE‐DPTT‐ICP NPs enable deep‐brain 3PF imaging of subcortical structures excited at both the two windows, reaching depths of 1640 and 880 µm below the brain surface, respectively. TPE‐DPTT‐ICP NPs are thus a versatile material simultaneously catering to the need at two infrared optical windows with deep tissue penetration. [ABSTRACT FROM AUTHOR]

2H phase tungsten diselenide (WSe2) is a p‐type 2D semiconductor from the transition metal dichalcogenides (TMDs) family with unique optoelectrical properties. Solution phase production of atomically thin WSe2 is challenging due to its instability under ambient conditions. We present a highly efficient and scalable solution method for simultaneously exfoliating and functionalizing WSe2 by leveraging the non‐covalent interaction between mercapto‐group and bulk WSe2. Single and few‐layer 2H phase pure WSe2 sheets of lateral size up to 5 μm with minimal basal plane defects, as revealed by XPS, Raman and FTIR spectroscopy, are produced in a water‐ethanol mixture. Remarkably, WSe2 dispersion remains stable even at high concentrations (10 mg/mL) and exhibited high colloidal stability with a shelf‐life exceeding a year. The findings from our study suggest that through precise manipulation of intercalation chemistry, mass production of solution‐processable phase‐sensitive 2D materials such as WSe2 can be achieved. This advancement holds great potential for facilitating their practical utilization in various real‐world applications. [ABSTRACT FROM AUTHOR]

Gold nanoparticles capping with three types of natural cyclodextrins are synthesized, allowing for precise control over their sizes ranging from 9 to 20 nm. These nanoparticles exhibit remarkable colloidal stability during long‐term storage, as well as excellent tolerance to saline, acidic, and alkaline conditions. Importantly, the assembly of nanoparticles is performed by using the silica nanospheres functionalized with cinnamyl group and the gold nanoparticle capping with three types of cyclodextrin, highlighting the selective formation of core‐satellite superstructure based on the host–guest molecular recognition on nano‐surface between different nanoparticles. [ABSTRACT FROM AUTHOR]

Theranostics integrating therapeutic power and imaging exhibit great prospects in precision medicine. It is a big challenge to develop simple and selective theranostic systems for potential clinical translation. Herein the Fe (III) driven assembly of chlorin E6 (Ce6) is reported to form multifunctional nanoparticles. The resulting Fe‐Ce6 NPs possess high loading content of photosensitizer Ce6, red‐shifted absorption, good colloidal stability, and photostability, and robust photothermal performance. After cellular internalization, Fe‐Ce6 NPs can respond to intracellularly enriched glutathione to release Ce6, thus priming photodynamic therapy (PDT) effect, fluorescence, and afterglow luminescence. In vitro and in vivo results prove that Fe‐Ce6 NPs remarkably enhance the tumor regression through photothermal therapy and in situ PDT. This study provides a facile and efficient method to construct versatile nanotheranostics for tumor treatment. [ABSTRACT FROM AUTHOR]

Perovskite nanocrystals (PNCs) are attractive photoactive materials in various optoelectronic devices including light‐emitting diodes, solar cells, and photodetectors. However, the weakly bound surface ligands on PNCs reduce colloidal stability and cause film formation and patterning difficulties, severely restricting their practical applications. Herein, a rationally designed photocrosslinkable zwitterionic (PZ) ligand is introduced to obtain directly patternable CsPbBr3 PNCs with enhanced colloidal stability, optical properties, and self‐assembly propensity. The PZ ligands strongly interact with the pre‐synthesized PNCs in solution, substantially replacing the original capping ligands and effectively passivating surface defects. This surface engineering induces strong electrostatic interactions between the PNCs, enabling the fabrication of densely packed CsPbBr3 PNC films. Furthermore, the methacrylate group of the PZ ligands serves as a bridge for active radical propagation in the ligand shells around the PNCs upon UV exposure. Accordingly, high‐resolution direct photopatterning can be achieved through ligand crosslinking, and the resulting PNC patterns (minimum line spacing of 4 µm) maintain optical stability for over 2 weeks. Therefore, this study demonstrates that a tailored ligand design strategy enables the simultaneous achievement of high colloidal stability, optical properties, photopatternability, and self‐assembly propensity and has considerable potential to be extended to other PNC materials. [ABSTRACT FROM AUTHOR]

Herein, biotin (Bio)‐conjugated poly(acrylic acid) (PAA)‐grafted ultrasmall gadolinium oxide nanoparticles (Bio‐PAA‐Gd2O3 NPs) were synthesized for enhanced tumor imaging using Bio as a tumor‐targeting ligand. The average particle diameter of Gd2O3 NPs was 2.1 nm. The Bio‐PAA‐Gd2O3 NPs exhibited excellent colloidal stability (i. e., no precipitation) and a high longitudinal water proton spin relaxivity (r1) of 23.8 s−1 mM−1 (r2/r1=1.6 and r2=transverse water proton spin relaxivity), which was ∼6 times higher than those of commercial Gd‐chelated magnetic resonance imaging (MRI) contrast agents. Cytotoxicity tests using two cell lines showed that the Bio‐PAA‐Gd2O3 NPs were almost non‐toxic up to the measured concentration of 500 μM Gd. The enhanced tumor imaging of the Bio‐PAA‐Gd2O3 NPs was demonstrated through their higher positive contrasts and longer contrast retention at the tumor after intravenous injection in T1 MR images, compared with those of the control PAA‐Gd2O3 NPs. [ABSTRACT FROM AUTHOR]