Search

In this study, MOF-74 nanocarriers were coated with sodium alginate (SALG) to enhance physicochemical properties and biocompatibility. Spectroscopic and microscopic analyses showed MOF-74 particle size below 100 nm. Zinc-based MOF-74 nanocarriers (Zn-MOF-74) were developed for doxorubicin (DOX) delivery, achieving high drug loading efficiency (DLE) and drug loading capacity (DLC) as measured by UV–visible spectrometry. Nanocarriers synthesized using zinc acetate (RA-MOF-74) achieved a DLE of 96.5% and a DLC of 19.6%, outperforming those prepared with zinc nitrate (RN-MOF-74) with a DLE of 88.8% and a DLC of 18.3%. Uncoated samples released cargo rapidly at pH 1.5 and significantly at pH 8. In contrast, SALG-coated samples showed reduced release at pH 1.5 and reached 54.2% release at pH 8 due to alginate's physicochemical properties. Drug release from DOX@RA-MOF-74/ALG was significantly slower and more sustained than from uncoated samples. This study demonstrates the potential of SALG-coated RA-MOF-74 as a controlled drug release system for biomedical applications. [ABSTRACT FROM AUTHOR]

Understanding oriented strand board combustion enhances safety guidelines and widens its uses with effective fire protection. This study developed a comprehensive mathematical model for the combustion of oriented strand board through cone calorimetry tests to accurately predict the heat release rate using COMSOL Multiphysics®. The model incorporates a kinetic mechanism for multi-step consecutive reactions, the formation of growing char, as well as mass and heat transport phenomena occurring during the oriented strand board combustion. Upon subjecting oriented strand board to heat, it undergoes combustion, resulting in the production of gas and char as the primary decomposition products. This char layer serves as a protective barrier, shielding the underlying material from further combustion. Additionally, increasing heat flux resulted in a higher heat release peak and a reduced time to ignition, indicating a significant influence of heat flow during fire initiation and promotion stages. Moreover, higher heat flux led to a shorter flame burning duration and accelerated the sample's burning rate. Increasing gas diffusivity through the char raises the peak heat release rate and shifts the plateau region upwards. Similarly, reducing char thickness boosts the peak heat release rate. The validation process showed a satisfactory agreement between the three datasets, supporting the accuracy of the numerical methodology. [ABSTRACT FROM AUTHOR]

This research aims to find an effective method to incorporate the anti-inflammatory drug naproxen (NAP) into a prototype zirconium metal–organic frameworks nanohybrid (Zr-MOF@NAP) and aloe vera (AV) biopolymer (Zr-MOF@NAP/AV) as a specific intestinal delivery vehicle. NAP entrapment efficiency and loading capacity were found to be 87.0% and 44.0%, respectively (Zr-MOF@NAP/AV). During the initial 2 h in the simulated stomach media, Zr-MOF@NAP released about 100% of the loaded NAP. Zr-MOF@NAP was coated with AV in order to overcome this challenge. As a result of the pH-responsive nature of AV, Zr-MOF@NAP/AV showed limited drug release at pH 1.2 and a higher percentage of drug release at pH 6.8 and 7.4. MTT assay was used to determine the in vitro cytotoxicity of Zr-MOF@NAP and Zr-MOF@NAP/AV against human fibroblast cells (HFFF2), and these results showed good cytocompatibility. [ABSTRACT FROM AUTHOR]

The beginning of the twenty-first century saw advancements in all areas of life, including medicine and nanotechnology. This review will look at the most recent advances in nanomaterials for diagnostics and treatments. The emphasis is on the application of nanofibers, nanosensors, and quantum dots (QDs) in medication delivery, neuron regeneration, chemical detection, and microelectrode probes. The manufacture of implantable nanofibers and nanosensors based on QDs, and their application-specific features impacting the interface with targeted brain cells were described. The collaborative efforts have helped us to understand the potential of nanostructured materials in fabrication to overcome the limits of micro and bulk materials in treatments and diagnostics. These advancements will eventually lead to using nanostructures, including nanofibers and nanosensors, in high throughput cutting-edge applications. Only when extensive safety investigations have been completed may the use of nanomaterials on an industrial basis be viable. This review discusses the recent advances in the usage of nanostructures and nanoparticles (NPs) for diagnostics and treatments, with a special focus on nanofibers, nanosensors, and quantum dots (QDs) applications in drug delivery, nerve regeneration, chemical detection, and microelectrode probes. [ABSTRACT FROM AUTHOR]

In this work, apigenin was chosen as a raw material to synthesize a novel epoxy monomer (DGEA), while the bio-based epoxy resin was further obtained after curing with 4,4′-diaminodiphenylmethane (DDM). The control samples were prepared by curing diglycidyl ether of bisphenol A (DGEBA) with DDM. The non-isothermal differential scanning calorimeter (DSC) method was utilized to further investigate the curing behavior and curing kinetics of the DGEA/DDM system. Despite no flame retardant active elements, the DGEA/DDM thermoset still exhibited exceptional anti-flammability. Specifically, the DGEA/DDM thermoset reached a V-0 rating in the UL-94 test and owned a high limiting oxygen index (LOI) value of 37.0%, while DGEBA/DDM resins were consumed completely in the vertical combustion test with a low LOI of 23.0%. Furthermore, the microscale combustion calorimetry (MCC) results manifested that compared with DGEBA/DDM resins, both PHRR and THR values of the DGEA/DDM resins were dropped by 84.0% and 57.6%, respectively. Additionally, the DGEA/DDM resin also presented higher storage modulus and tensile strength compared with DGEBA/DDM one. Particularly, in contrast with that of the cured DGEBA/DDM one (156 °C), the DGEA/DDM thermoset displayed an extremely high glass transition temperature (232 °C). This study breaks new ground on how to produce bio-based monomers with aromatic structures and achieve high-performance thermosetting polymers. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks are the new type of crystalline porous materials with specific properties such as appropriate catalytic activity, accessible surface area, tunable pore structure, as well as stable chemical and thermal properties. In this study, solvothermal preparation of a copper-metal organic framework (HKUST; Hong Kong University of Science and Technology) was used to load baclofen as a model drug. Baclofen-HKUST-1 was employed to increase the drug release controllability of bio-polymeric carboxymethyl cellulose (CMC) hydrogel under the gastrointestinal tract (GIT). Results from in vitro drug delivery and kinetic assessments revealed that CMC/baclofen-HKUST-1 bio-nanocomposite could better act against stomach pH; it also increased the releasing homogeneity and drug delivery under GIT conditions. Also, MTT assay demonstrated there was considerable cytotoxicity against human colon cells associated with CMC/baclofen-HKUST-1 bio-nanocomposite. According to the findings of CMC/baclofen-HKUST-1 bio-nanocomposite assessments, the mentioned component could be applied to drug administration. [ABSTRACT FROM AUTHOR]

Wildfires have been recognized as a natural incident in some forests, however, fire season is now more severe and extensive, even in tropical rainforests in which fire could have damaging impacts. A hydrogel is a 3-D polymeric structure encompassing cross-linked and hydrophilic macromolecules. In comparison with water, hydrogels have shown some superiorities in terms of water-binding, cooling, and sealing, which make them be applied in forest fire prevention programs for improving fire-extinguishing performance. In this study, an environmentally friendly phosphorus-modified methylcellulose/silica hybrid hydrogel was prepared based on the modified methylcellulose by 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide–itaconic acid (DOPO-ITA) and silica nanoparticles. In the fire prevention experiments, the grass treated with the methylcellulose@DOPO-ITA@silica hybrid hydrogel shows self-extinguishing behavior, whereas those treated with ordinary water or methylcellulose hydrogel can be easily ignited after one week. In the firefighting experiments, the methylcellulose@DOPO-ITA@silica hybrid hydrogel displays a much shorter extinguishing time and lower consumption volume than ordinary water and the methylcellulose@DOPO-ITA hydrogel. This work presents an environmentally friendly, non-toxic, and biodegradable cellulose-based hybrid hydrogel for the fire prevention and firefighting of wildfires. [ABSTRACT FROM AUTHOR]

The current study is carried out on curcumin delivery, which is recognized as an anticancer drug, to cancerous cells through a bio-metal–organic framework (bioMOF). After being immersed within the drug solution, the process of curcumin encapsulation was conducted in the porous bio-MOF-11. Furthermore, both protecting and carrying curcumin encapsulated bio-MOF-11 nanohybrid (curcumin@bio-MOF-11) within the gastrointestinal tract (GIT) were carried out using pH-sensitive pectin biopolymer. There were two different approaches applied to identify the pectin-coated curcumin@bio-MOF-11bio-nanocomposite hydrogel bead (pectin/curcumin@bio-MOF-11). Using the simulated GIT conditions, in-vitro drug release tests were conducted to illustrate the pectin/curcumin@bio-MOF-11effectiveness that was applied to the process of curcumin controlled delivery as a new carrier. Consequently, results showed that there was a constant release associated with pectin/curcumin@bio-MOF-11 under GIT conditions. Moreover, considerable toxicity of pectin/curcumin@bio-MOF-11 against human colon carcinoma cells was confirmed through the MTT test. Results implied that provided bio-nanocomposite hydrogel beads could act as appropriate drug delivery systems of curcumin colonic drug release. [ABSTRACT FROM AUTHOR]

Since nanoparticle-based treatment methods could decrease the side effects of conventional therapeutics; they have been considered as important approaches. One of the main drug delivery systems associated with easy preparation, decreased cytotoxicity, appropriate biocompatibility and drug loading capacity, and reduced cost is inorganic layered zinc hydroxides (LZH) as anionic clays, which is a member of layered hydroxide salts. It is found that LZH contains a layered structure and high surface-to-volume ratio; therefore, it could lead to the treatment agent's interpolation and deliverance to the desired point and consequently, reduction of side effects. It should also be noted that the prevalence of drug release could be reduced as a result of the continuous intercalation of drug delivery. The current study investigates the promotions of LZH composition, characteristics, development manner, and drug administration. Furthermore, it represents useful data regarding LZH and drug delivery. [ABSTRACT FROM AUTHOR]

Fabrics with high flame-retardancy have been extensively applied for numerous applications including textile, garments, automobile industries, pants, shirts, suits bed sheets, and indoor decorations. Coatings consisting of ammonium hexametaphosphate (NH4-HMP), laponite (LAP), and hexadecyltrimethoxysilane were synthesized through sol–gel method; they were then employed on the cotton fabrics to enhance their hydrophobicity and flame retardancy. The influences of LAP concentration on fire-retardancy of the samples were evaluated. The combustion behavior, morphological structures, thermal stability, and hydrophobic properties of the cotton fabrics were studied. Results indicated the excellent flame retardant property of the treated cotton fabrics as they immediately extinguished upon removal of the flame source. The limiting oxygen index of the treated cotton was enhanced to 29% in comparison to that of the pure one (19.5%). The findings also indicated that a higher concentration of LAP is useful for improving flame retardancy of the coated substrate. In addition, the hydrophobicity of the fabric surface was measured by a water contact angle of 138°, while its superoleophilicity was assessed by an oil contact angle of 0°. To separate water–oil mixtures, the as-prepared cotton sample was utilized as operative substances. Overall, in this study a facile technique is provided for preparing cotton fabrics with considerably enhanced flame retardancy and superior self-cleaning features toward different fluids making them suitable as a promising candidate for water–oil separation. [ABSTRACT FROM AUTHOR]

In the current study, Zeolitic Imidazole Framework-8 (ZIF-8) was in situ grown on the surface of cellulose fibers and the ZIF-8@cellulose composite aerogels were fabricated by a freeze-drying method. The flame-retardant, thermal and mechanical characteristics of the cellulose-based aerogels were investigated. SEM images indicated that ZIF-8 was evenly deposited on the surface of the cellulose fibers in the aerogel owing to formation of hydrogen bonding with cellulose molecules. The addition of ZIF-8 enhanced thermal stability and flame retardancy of the host cellulose aerogel. The peak of heat release rate of the ZIF-8@cellulose-3 composite aerogel exhibited a drastic decline from 128 W g−1 to 63 W g−1 and the total heat release from 25.9 kJ g−1 to 14.8 kJ g−1. In the UL-94 vertical burning test, the samples showed self-extinguishing behavior. Additionally, ZIF-8 induced a dramatic enhancement in the mechanical properties of the host cellulose. Specifically, the compressive stress of the ZIF-8@cellulose composite aerogel showed a significant increase from 0.45 to 34.80 MPa. Moreover, the ZIF-8@cellulose composite aerogel can selectively remove the organic pollutants from water and adsorb a wide range of liquid oils with considerable capacities. The current study presented a feasible approach to synthesis of strong and flame-retardant cellulose-based aerogels for waste water purification. [ABSTRACT FROM AUTHOR]

Non-steroidal anti-inflammatory drugs are a broad class of agents with analgesic and anti-inflammatory properties. Despite their frequent current uses, they exhibit several problems for administration related to delivery control, low solubility, and low oral bioavailability. Due to mentioned reasons, several inorganic materials (anionic clays and mesoporous materials) as host, have been tested to support the min order to overcome these drawbacks. Among these materials, layered zinc hydroxide (LZH) has been used in recent years. In the present research, naproxen (Np) was intercalated into the interlayer space of LZH using anion exchange method. From the PXRD results, it was found that Np anions were successfully incorporated on LZH and the basal spacing of LZH increased from 9.57 to 22.09 Å, indicating that Np was intercalated into the interlayer space of LZHs as a monolayer. FTIR study exhibits the vibrations bands of the functional groups of Np and of the LZH, confirming the intercalation. TG analysis confirms that the intercalated Np drug in the form of nanohybrid is thermally more stable than its Np salt. SEM images illustrated that the LZH precursor has a plate-like structure transformed into the uniform structure when the nanohybrid is formed. In vitro drug release experiments at a pH of 7.4 phosphate buffer solutions and a pH of 4.8 acetate buffer solution showed controlled release profiles with Np anions as a non-steroidal anti-inflammatory model drug. In the following, the results of cytotoxicity assay showed that Np–LZH nanohybrid affected cell viability in a dose and time-dependent mode. According to the results, synthesized LZH can act as a host network and accept Np as a guest in its structure and release the drug in a more controlled manner and over a longer period of time. [ABSTRACT FROM AUTHOR]

New drug delivery systems are very helpful in diagnosis and treatment of diseases through controlled and targeted drug delivery. They can increase bioavailability of drugs and reduce their side effects. Metal-organic frameworks (MOFs) are alternative drug delivery systems, which are suitable for targeted drug delivery due to their adjustable pore sizes and compatibility by adding some functional groups. Application of these compounds permits simultaneous use of several advantages including biocompatibility, the ability to absorb large amounts of drugs and control drug release. The present study was designed to provide Zn2(bdc)2(dabco) MOF and evaluate its performance in absorbing and releasing gentamicin. Characterization methods, such as FTIR, XRD, SEM, BET, UV-Vis spectroscopy and TGA, were employed to characterize the gentamicin-loaded Zn2(bdc)2(dabco) structure. The amount of drug release from Zn2(bdc)2(dabco) was measured in buffer solutions with 7.4 and 5.0 pHs. Furthermore, antibacterial properties of the drug, MOF and drug-loaded MOF have been investigated against Gram-positive and Gram-negative bacteria. This study shows the potential of using Zn2(bdc)2(dabco) frameworks for controlled release of antibiotic drugs. [ABSTRACT FROM AUTHOR]

In this study, a simple method was developed to prepare gentamaicin (GEN)—loaded nanoscale zeolitic imidazolate framework-8 (GEN@NZIF-8) nanoparticles (NPs) at room temperature and GEN@NZIF-8 NPs were characterized by FT-IR spectroscopy, powder X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, BET nitrogen adsorption-desorption, and UV-Vis spectroscopy. The PXRD patterns showed that large drug molecules can be encapsulated in ZIF-8 frameworks. Thermogravimetric analysis confirms that the GEN@NZIF-8 NPs have higher thermal stability than ZIF-8 NPs. FT-IR spectroscopy exhibted the presence of functional groups of GEN and NZIF-8 frameworks in GEN@NZIF-8 NPs. Results showed that GEN@NZIF-8 NPs exhibited high drug capacity (19%) and high drug loading capacity of gentamicin anions through ion exchange and good chemical stability. The researchers attempted to demonstrate that large drug molecules at pH 5.0 and 7.4 could be loaded in NZIF-8 NPs. Additionally, drug release in acidic condition was faster than in physiological condition. The biological activities of GEN, NZIF-8 and GEN@NZIF-8 NPs against Gram-positive and Gram-negative bacteria showed that the GEN@NZIF-8 NPs had good antimicrobial activity. This work highlights the potential of using NZIF-8 as a valuable candidate to develop highly efficient drug delivery vehicles in the treatment of infectious diseases using pH-responsive release. [ABSTRACT FROM AUTHOR]

The intercalation of fluoroquinolone antibiotic, Gemifloxacin (GEM) anions, into layered zinc hydroxide (LZH) has been achieved by using ion-exchange method. The GEM-LZH/Chitosan nanocomposite coating Chitosan nanocomposite was prepared in alkaline aqueous solution. Powder X-ray diffraction studies confirmed a basal spacing of 25.54 Å, showing that the GEM was successfully intercalated into the LZH interlayer. The arrangement of GEM anions was in a monolayer form between the LZH interlayers. Fourier transform infrared spectroscopy results exhibited the formation of the host-guest nanohybrid without any change in the structure of the GEM. The increased thermal stability of nanohybrid was confirmed by thermal analyses. The in vitro release study of GEM from nanohybrid and nanocomposite was investigated in phosphate buffer saline solution of pH 4.8 and 7.4 using ultraviolet-Visible spectroscopy. [ABSTRACT FROM AUTHOR]

The nonsteroidal anti-inflammatory drug (NSAID), ibuprofen (IBU) anion, was intercalated into the layered zinc hydroxide (LZH) to form a new organic-inorganic nanohybrid. Then, IBU-LZH nanohybrid was dispersed into chitosan for the formation of the nanocomposite. The IBU-LZH nanohybrid was characterized by powder X-ray diffraction (PXRD) to study intercalation, scanning electron microscopy (SEM) for the investigation of surface morphology, Fourier transform infrared (FTIR) spectrophotometer to study the chemical interactions and thermal gravimetric analysis/derivative thermogravimetric analysis (TGA/DTG) for understanding the thermal stability. The PXRD patterns showed that the IBU was successfully intercalated into the interlay space of LZHs as monolayers and the basal spacing of LZH increased from 9.57 to 19.54 Å. The FTIR analyses confirmed the formation of the host-guest nanohybrid. The DTG studies revealed that the thermal stability of IBU was increased after the intercalation into LZH. The in vitro release study of IBU from IBU-LZH and IBU-LZH/chitosan nanocomposite was investigated in phosphate buffer saline (PBS) solution of pH 4.8 and 7.4. The drug release from the LZH was studied by ultraviolet-visible (UV-vis) spectroscopy. [ABSTRACT FROM AUTHOR]

The anti-inflammatory drug, Diclofenac (DIC) anion, was intercalated into the layered zinc hydroxide (LZH) by ion-exchange method. Then, the DIC-LZH/Chitosan nanocomposite was prepared by coating of Chitosan on DIC-LZH. LZH intercalated with DIC was successfully encapsulated into Chitosan by precipitation method. The structures of the obtained products were studied by powder X-ray diffraction, FT-IR spectroscopy, scanning electron microscopy, and thermal analysis. The XRD patterns and FTIR analyses showed that the DIC was successfully intercalated into the LZH interlayer space with an average basal spacing of 29.42 Å. Thermal analysis studies confirmed that the thermal stability of DIC was enhanced after intercalation into LZH. In addition, drug release behaviors in vitro of DIC from DIC-LZH and DIC-LZH/Chitosan nanocomposites were observed in phosphate buffer solution under the conditions of pH 4.8 and 7.4, respectively. [ABSTRACT FROM AUTHOR]

Layered zinc hydroxide (LZH) nanoparticles are versatile material used for intercalating bioactive and therapeutic molecules with the purpose of obtaining controlled release properties, enhancing their poor aqueous solubility and protecting them from degradation. Co-precipitation method was employed here to synthesis LZH and ion-exchange intercalation of the anti-inflammatory drug mefenamic acid (MA) to prepare MA–LZH nanohybrids. An increase in the basal spacing of the (200) plane from 9.57 Å in pristine LZH to 17.73 Å in the MA–LZH nanohybrid indicated successful intercalation of anionic MA into a LZH gallery, which was arranged in a monolayer fashion with the carboxylate group pointing toward the LZH inorganic interlayers. Fourier-transform infrared spectroscopy confirmed successful intercalation without major changes in the structure of MA. Thermogravimetric analysis results showed that MA is stabilized in the interlayers through electrostatic interaction of MA within the interlayer space of LZH. The drug released from the nanohybrid revealed a controlled profile of about 66% of MA anions released at pH 7.4, while 86% release took place after 14 h at pH 4.8. The mechanism of drug release was explained by the Korsmeyer–Peppas kinetic models. The kinetic studies suggest that drug release mechanism is predominantly diffusion-controlled. In vitro tests performed with normal fibroblast cells indicated synergistic anti-inflammatory performance compared to pristine LZH and pure MA; hence, MA–LZH nanohybrid effectively affected controlled-release performance. Because of ease of preparation and sustained release of the active and less-toxic compounds to the cell, this nanohybrid could be regarded as a potential drug delivery system. [ABSTRACT FROM AUTHOR]

While MOF-74 drug delivery platforms are known for their high drug loading capacity (DLC) and efficiency (DLE), surface chemistry modifications can further enhance their performance. Two variants of Zn-MOF-74 nanoparticles (particle size < 100 nm, per microscopic analysis) were prepared at room temperature, fully characterized and loaded with doxorubicin (DOX) as a model drug. UV-visible spectrometry revealed a DLE of 96.5% and a DLC of 19.6% for zinc acetate (RA-MOF-74) nanocarrier, against zinc nitrate (RN-MOF-74) with 88.8% and 18.3% in the same order. RA-MOF-74 nanocarriers were coated with polydopamine (PDA) through an in-situ polymerization process to enhance physicochemical properties and compatibility with biological systems. Both the uncoated and PDA-coated RA-MOF-74 showed accelerated drug release at pH 5.5 due to quicker structural collapse, which experienced an increase of 24.3% for the former and a 6.2% increase for the latter sample. The biological properties of loaded Zn-MOF-74 nanocarriers demonstrated acceptable anti-cancer activity, and possessing low hemolytic activity. Moreover, the cytotoxicity results indicated an inhibition of 85.73% against MDA-MB-231 breast cancer cells for the DOX-loaded MOF-74, notably about 5% higher than that of the pure DOX at a concentration of 400 µg/ml. At the same concentration, loaded MOF-74 showed a hemolytic activity of 9.62%, which was significantly lower than 28.97% assigned to the pure DOX. These results demonstrate the potential of Zn-MOF-74 nanoparticles for diverse medical applications, warranting further investigation of their in vivo performance in both therapeutic and diagnostic roles. [ABSTRACT FROM AUTHOR]