Hydroxypropyl Methylcellulose Research Articles

Facile one-pot synthesis and characterization of ZnSe/HPMC nanocomposites

Herein, we report the facile synthesis of ZnSe/HPMC (Hydroxypropyl Methyl Cellulose) nanocomposites by in-situ method. The biodegradable HPMC polymer acts as capping molecule as well as polymer matrix. The optical and structural properties of ZnSe/HPMC nanocomposites were studied by optical absorption, photoluminescence (PL) spectroscopy, FTIR, XRD and TEM measurements. Size of the ZnSe nanoparticles was tuned by controlling the pH of the reaction. As prepared ZnSe nanoparticles were spherical in shape, homogeneously distributed in the polymer and XRD patterns exhibit face centred cubic phase. The present method is a novel approach for the synthesis of ZnSe nanoparticles using HPMC as a capping molecule as well as matrix to develop nanocomposite.

Utilizing foam-structured hydroxypropyl methylcellulose oleogels with curcumin for deep-fried chicken nuggets in carnauba wax-canola oil oleogel

In this study, foam-structured hydroxypropyl methylcellulose was used to structure cod liver oil into oleogel. Different concentrations of curcumin (0, 1.1, 2.2, 3.3, and 4.4 mg/100g of chicken nuggets) were added to the oleogels and incorporated into the chicken nuggets. Subsequently, samples were deep-fried in an oleogel frying medium prepared with carnauba wax and canola oil (10g/100g). Our results revealed that the addition of 4.4 mg/100g of curcumin led to the highest fat uptake reduction and moisture retention compared to the control and 1.1 mg/100g of curcumin (P < 0.05). Additionally, the addition of 4.4 mg/100g of curcumin exhibited consistently higher oxidative stability, as indicated by thiobarbituric acid reactive substances (TBARS), during the 30-day storage period at −18 °C compared to the control (P < 0.05). Notably, treated samples did not show any alteration in ash and protein contents, color, texture, pH values, sensory attributes, or microscopic structures of the fried chicken products. Furthermore, fatty acid analysis revealed that the samples containing 4.4 mg/100g of curcumin had significantly lower levels of saturated fatty acids and higher levels of monounsaturated and polyunsaturated fatty acids than the control (P < 0.05). Overall, the study demonstrates that adding curcumin in a carrier setting to deep-fried chicken products can improve the products by reducing fat uptake and extending oxidative stability.

Composite Materials Based on Biocompatible Metal-Organic Framework and Anthocyanins from Hibiscus sabdariffa for Active Food Packaging

The biocompatible metal-organic framework [Zn4(GA)4(H2O)4] · 4H2O (H2GA = glutamic acid) was used as a container for anthocyanins from Hibiscus sabdariffa in composite films based on kappa-carrageenan and hydroxypropyl methylcellulose. The obtained composite materials showed high antioxidant activity and ability to undergo pH-induced color change upon reactions with gaseous products of pathogen development and, hence, possess the potential for practical application as functional materials for food packaging.

Essential Oil Components Incorporated Emulsion Hydrogels for Eradicating Dermatophytosis Caused by Pathogenic Fungi Trichophyton mentagrophytes and Microsporum canis.

Dermatophytosis is a prevalent fungal infection and public health burden, majorly caused by the attack of zoophilic fungi genera of Trichophyton and Microsporum. Among them, T. mentagrophytes and M. canis are the dominating pathogens that cause dermatophytosis in humans. Though anti-fungal treatments are available, the widespread drug resistance and minimal efficacy of conventional therapies cause recurring infections. In addition, prolonged anti-fungal medications induce several systemic side effects, including hepatotoxicity and leucopenia. The anti-dermatophytic formulation of biocompatible essential oil components (EOCs) is attractive due to their highly potent anti-dermatophytic action. Herein, two EOCs, Eugenol (EU) and Isoeugenol (IU), incorporated emulsion hydrogel (EOCs-EHG) synthesized from hydroxypropylmethyl cellulose and poly(ethylene glycol) methyl ether methacrylate. The cytocompatibility of the hydrogels is confirmed by treating them with fibroblast and keratinocyte cell lines. The EOCs-EHG demonstrated pH and temperature-responsive sustained release of entrapped EOCs and inhibited fungal spore germination. T. mentagrophytes and M. canis biofilms are eradicated at a minimal inhibitory concentration of 2µg mL-1 each of EU and IU. The in vivo anti-dermatophytic activity of EOCs-EHG is confirmed in dermatophyte-infected Wistar albino rat models. The topical application of EOCs-EHG demonstrated complete infection eradication and facilitated skin regeneration, emphasizing the therapeutic potential of EOCs-EHG against dermatophytosis.

Improving oral delivery of ciprofloxacin through in situ spray drying and acid counterions

This study explores the application of a novel three-fluid nozzle spray drying technique in formulating in situ ciprofloxacin (CFX) salts for improved oral drug delivery. The used key materials in the study include CFX combined with four different counterions: succinic acid (SA), glutaric acid (GA), adipic acid (AA), and pimelic acid (PA), alongside hydroxypropyl methylcellulose (HPMC) as a matrix agent. The process utilized a three-fluid nozzle spray drying technique to produce CFX salts directly with these acids during the process, creating three types of formulations: pure salts (SALT), solutions of drug and polymer (SOL), and nanoprecipitates of drug within a polymer matrix (SUS). Powder X-ray Diffraction (PXRD) and Scanning Electron Microscopy (SEM) analyses revealed that the formulations predominantly exhibited an amorphous structure with varied particle shapes and sizes. The dissolution profiles of CFX salts show a marked burst release within the initial 5 min, with CFX-GA leading at nearly double the release rate of CFX-AA, after which all formulations rapidly achieve over 90 % dissolution and maintain a stable release up to 30 min. This pattern was attributed to the interactions between the drug salts and HPMC, resulting in a sustained release of CFX. In vivo experiments with rabbits revealed a higher plasma concentration of CFX for CGAH-sus compared to CGAH-sol, highlighting the enhanced bioavailability of the SUS formulation. The amorphous nature of CGAH-sus, with ionization confirmed through Raman spectroscopy, facilitated efficient drug release and absorption in the gastrointestinal tract. This study illustrates the effectiveness of the three-fluid nozzle spray drying method in producing salts with varied physical properties and dissolution profiles, holding potential for advanced oral drug delivery systems.

FORMULATION OF PROPOLIS-BASED RECURRENT APHTHOUS STOMATITIS (RAS) PROTECTIVE PATCH WITH COMBINATION OF PVP AND CELLULOSE MATERIALS

Objective: The objective of this study was to obtain a mucoadhesive patch for recurrent aphthous stomatitis (RAS) with propolis, proven propolis’ antibacterial ability against bacteria in the oral cavity, and to obtain the physical characteristics of the produced patch. Methods: The patch was produced using a solvent-casting method. The antibacterial properties were determined by the disc diffusion method against S. mutans, S. oralis, S. sanguinis, and S. gingivalis. The physical characteristics of the patch was determined by examining weight and thickness dimension, swelling, surface pH, and structure observation. Results: The patch was made from 8 formulations with different propolis concentrations, Polyvinylpyrrolidone (PVP), and the use of cellulose materials (Hydroxypropyl methylcellulose and Carboxymethylcellulose). The concentrations of propolis used were 3%, 5%, 7%, and 10%. While the ratio of PVP and cellulose material in the formulation is 2:1. Results showed that propolis had a zone of inhibition greater than 2 mm against S. oralis, S. sanguinis, S. mutans, and P. gingivalis bacteria. Patches produced were clear to brown-colored films with high swelling percentage due to hydrophilic polymers used. The patch thickness that is closest to the requirements of the buccal patch was F8 with 0.36+0.04 mm. The mean values of the patches have matched normal salivary pH of 5.5–7. Physically, PVP/CMC formulations were more sticky, and the PVP/HPMC patches were more solid and stronger. Conclusion: A mucoadhesive patch was obtained with a combination of PVP/CMC and PVP/HPMC, tween 80 as a surfactant, glycerin as a plasticizer, peppermint oil as a flavor enhancer and preservative, with the active ingredient propolis.

Feasibility of underwater 3D printing: Effects of anti-washout admixtures on printability and strength of mortar

The dispersion and reduction in strength of concrete underwater pose significant challenges to advancing underwater 3D concrete printing technology. While employing anti-washout admixtures holds promise, there is a dearth of relevant research. Herein, a study using various potential anti-washout admixtures, such as micro silica (MS), nano silica (NS), glass fibers (GF), and hydroxypropyl methyl cellulose (HPMC), in mortar mixes was conducted. These mortar mixes were then printed underwater, and their performance in both fresh and hardened states was evaluated to develop underwater 3D printable mortars. The findings revealed that both MS and NS enhance the washout resistance, extrudability, and buildability of fresh mortar, while also improving the flexural, compressive, and bond strengths of hardened mortar. HPMC enhances underwater printability and bond strength, although it may negatively impact flexural and compressive strengths. GF exhibits adverse effects on underwater printability and mechanical properties and is incompatible with HPMC. Noticeably, the combination of MS, NS, and HPMC greatly enhances underwater printability (no dispersion and lowest extrudability/buildability variation coefficients) and mechanical properties (increasing flexural strength and bond strength by 21 % and 151 %, respectively). These findings led to the proposal of several mortar mixes deemed suitable for underwater 3D printing.

Rapid in-situ green synthesis and antibacterial properties of silver nanoparticles

In-situ green synthesis of silver nanoparticles (AgNPs) using hydroxypropyl-methylcellulose (HPMC) as a reducing and stabilizing agent is presented in this paper. A simple solution-casting method is used for preparing nanocomposite films. The reduction of silver ions to silver elementary particles was completed when the alkaline pH was maintained. The initial confirmation of AgNPs was visualized by the brown color of the prepared solution and later confirmed by the surface Plasmon resonance peak obtained from the UV–visible absorption study. X-ray diffraction measurement study revealed the crystalline nature of the AgNPs with FCC structure. The uniform distribution of AgNPs in the HPMC matrix is witnessed by Scanning electron microscope. The spherical shape of the prepared AgNPs is observed by transmission electron microscopic images with an average size of 11 nm. Dynamic light scattering experiment exposed the hydrodynamic size distribution and good stability of AgNPs. Thermogravimetric analysis showed high thermal stability of nanocomposites. Mechanical studies showed increased elongation at break and tensile strength of the prepared nanocomposites. Dielectric constant and dielectric loss were ascertained to decrease with an increase in frequency. Further, the antibacterial activity study showed an excellent activity of AgNPs in contrast to human bacterial pathogens viz.,Staphylococcus aureusandEscherichia coli.

Development of Functional Composite Edible Films or Coatings for Fruits Preservation with Addition of Pomace Oil-Based Nanoemulsion for Enhanced Barrier Properties and Caffeine for Enhanced Antioxidant Activity.

The aim of this study was to develop functional composite edible films or coatings for fruit preservation by the addition of bioactive components in combinations that have not yet been thoroughly studied, according to the relevant literature. Edible films were initially composed of (i) chitosan (CH), cellulose nanocrystals (CNC) and beta-cyclodextrin (CD) (50%-37.5%-12.5% ratio), and (ii) hydroxypropyl methylcellulose (HPMC), cellulose nanocrystals (CNC) and beta-cyclodextrin (CD) (50%-37.5%-12.5% ratio). The bioactive components incorporated (5, 10 and 15% v/v) were as follows: (i) pomace oil-based nanoemulsion (NE) aiming to enhance barrier properties, and (ii) caffeine (C), aiming to enhance the antioxidant activity of films, respectively. Indeed, NE addition led to very high barrier properties (low oxygen and water vapor permeability), increased flexibility and reduced color. Furthermore, the contribution of these coatings to fresh strawberries' preservation under cold storage was investigated, with very promising results concerning weight loss, color difference, and preservation of fruit moisture and quantity of O2 and CO2 inside the packages. Additionally, C addition led to very high antioxidant activity, reduced color and improved barrier properties. Finally, the contribution of these coatings to avocado's preservation under cold storage was investigated, with very encouraging results for color difference, hardness and peroxide value of the fruit samples.

Preparation and systematic study of mechanical properties and suspension stability of polyurethane-polyurea double-shell perfume oil microcapsules

The perfume oil microcapsules are of considerable significance in personal care and household products due to their ability to control the targeted release of perfume oil under specific conditions, which enhances the longevity and overall performance of the product. In this study, double-shell perfume oil microcapsules were prepared using polyurea (PUA) and polyurethane (PU) as wall materials. The first PUA shell was formed at room temperature to encapsulate the perfume oil by adjusting the agitation speed, protective colloid concentration, and polymethylene polyphenyl isocyanate (PAPI) content. Subsequently, the second PU shell was formulated. Mechanical property analysis revealed that PU/PUA microcapsules exhibited superior characteristics, showing a threefold increase in mechanical strength compared to PUA microcapsules. Thermogravimetric analysis and dynamic release experiments in ethanol demonstrated that the PU/PUA microcapsules possessed higher thermal stability and greater compactness compared to the PUA microcapsules. Finally, by incorporating bacterial cellulose (BC) microgels and hydroxypropyl methylcellulose (HPMC) as stabilizing agents into the laundry detergent matrix (JJ), a stable suspension of PU/PUA microcapsules was achieved for over 180 days.

Long-lasting, UV shielding, and cellulose-based avermectin nano/micro spheres with dual smart stimuli-microenvironment responsiveness for Plutella xylostella control

The requirement to improve the efficiency of pesticide utilization has led to the development of sustainable and smart stimuli-responsive pesticide delivery systems. Herein, a novel avermectin nano/micro spheres (AVM@HPMC-Oxalate) with sensitive stimuli-response function target to the Lepidoptera pests midgut microenvironment (pH 8.0–9.5) was constructed using hydroxypropyl methylcellulose (HPMC) as the cost-effective and biodegradable material. The avermectin (AVM) loaded nano/micro sphere was achieved with high AVM loading capacity (up to 66.8 %). The simulated release experiment proved the rapid stimuli-responsive and pesticides release function in weak alkaline (pH 9) or cellulase environment, and the release kinetics were explained through release models and SEM characterization. Besides, the nano/micro sphere size made AVM@HPMC-Oxalate has higher foliar retention rate (1.6–2.1-fold higher than commercial formulation) which is beneficial for improving the utilization of pesticides. The in vivo bioassay proved that AVM@HPMC-Oxalate could achieve the long-term control of Plutella xylostella by extending UV shielding performance (9 fold higher than commercial formulation). After 3 h of irradiation, the mortality rate of P. xylostella treated by AVM@HPMC-Oxalate still up to 56.7 % ± 5.8 %. Moreover, AVM@HPMC-Oxalate was less toxic to non-target organisms, and the acute toxicity to zebrafish was reduced by 2-fold compared with AVM technical.

Amorphous Solid Dispersions: Implication of Method of Preparation and Physicochemical Properties of API and Excipients.

The present study investigated the effect of different polymers and manufacturing methods (hot melt extrusion, HME, and spray drying, SD) on the solid state, stability and pharmaceutical performance of amorphous solid dispersions. In the present manuscript, a combination of different binary amorphous solid dispersions containing 20% and 30% of drug loadings were prepared using SD and HME. The developed solid-state properties of the dispersions were evaluated using small- and wide-angle X-ray scattering (WAXS) and modulated differential scanning calorimetry (mDSC). The molecular interaction between the active pharmaceutical ingredients (APIs) and polymers were investigated via infrared (IR) and Raman spectroscopy. The in vitro release profile of the solid dispersions was also evaluated to compare the rate and extend of drug dissolution as a function of method of preparation. Thereafter, the effect of accelerated stability conditions on the physicochemical properties of the solid dispersions were also evaluated. The results demonstrated higher stability of Soluplus® (SOL) polymer-based solid dispersions as compared to hydroxypropyl methylcellulose (HPMC)-based solid dispersions. Moreover, the stability of the solid dispersions was found to be higher in the case of API having high glass transition temperature (Tg) and demonstrated higher interaction with the polymeric groups. Interestingly, the stability of the melt-extruded dispersions was found to be slightly higher as compared to the SD formulations. However, the down-processing of melt-extruded strands plays critical role in inducing the API crystal nuclei formation. In summary, the findings strongly indicate that the particulate properties significantly influence the performance of the product.

Development and In vitro Evaluation of Pantoprazole-Sustained Release Effervescent Floating Tablets for Effective Management of Ulcer

Introduction: Pantoprazole is a very suitable drug for the treatment of numerous acid-related conditions in humans and mammals. Owing to its short half-life (0.9 – 1.9 h), it is ideal for sustained release formulation. Methods: This study was aimed at developing pantoprazole gastroretentive (GR) controlledrelease tablets and to determine the effects of this formulation and processing parameters on drug release and other critical quality attributes of directly compressed tablets produced using different matrix-forming polymers, namely, Hydroxypropyl methylcellulose (HPMC), chitosan, sodium alginate, maize starch, kappa- carrageenan, and propyl vinyl pyrrolidine PVP K30 when formulated into effervescent Floating Drug Delivery Systems (FDDS). Results: The buoyancy lag time of less than 5 seconds and a total floating time of more than 12 hours for all batches is a good indication of achieved floatation for FDDS. Conclusion: Validation processes initiated with the five batches indicated that the polymer blends had the potential for the formulation of pantoprazole FDDS and, hence, could enhance patient compliance and better treatment outcomes due to their sustained release potentials.

Comparative Evaluation of Anterior Segment Optical Coherence Tomography Findings Following Accelerated Corneal Crosslinking Protocols Using Different Riboflavin Formulations and Soaking Durations

Purpose To comparatively evaluate the influence of different riboflavin formulations and soaking durations on the anterior segment optical coherence tomography (AS-OCT) findings following accelerated corneal crosslinking (ACXL) at 9 mW/cm2 for in progressive keratoconus. Methods In this prospective study, consecutive patients with progressive keratoconus were randomized into 4 groups. Group 1: hydroxypropyl methylcellulose (HPMC)-based riboflavin for 10 min; Group 2: HPMC-based riboflavin for 20 min; Group 3: dextran-based riboflavin (0.1%) for 30 min. Riboflavin soaking was followed by ultraviolet-A irradiation at 9 mW/cm2 for 10 min in all three groups. Group 4 underwent conventional CXL (CCXL) using Dresden protocol. The AS-OCT features of the crosslinked cornea were evaluated at postoperative month 1 and correlated to the clinical outcomes at postoperative month 12. Results The study enrolled 26 eyes of 26 patients in each group. In groups 1 and 2, the AS-OCT findings were similar (p > .05) and the demarcation lines depth (DLD) were deep as obtained following CCXL. The DLD was significantly shallower in group 3 compared to the other groups (p < .01). There were no between-group differences in regards to the visual, refractive, keratometric, and tomographic outcomes at postoperative month 12. No significant endothelial cell loss or any other clinically significant adverse event was encountered in any patient’s eye at 12 months follow-up. Conclusion Although structural variations were noted in the crosslinked cornea, DLDs observed following ACXL (9 mW/cm2) using HPMC-based solution for 10 or 20 min were similar to those observed following CCXL. Whereas, ACXL (9 mW/cm2) using dextran-based solution for 30 min resulted in the shallowest DLD. Despite these remodeling differences, the visual, refractive and tomographic outcomes of all groups were comparable at postoperative 1-year follow-up. Studies with a greater number of patients and longer follow-ups are required to establish any relation between AS-OCT characteristics of crosslinked cornea and ACXL efficacy.

Exploring biorelevant conditions and release profiles of ritonavir from HPMCAS-based amorphous solid dispersions

Development of a release test for amorphous solid dispersions (ASDs) that is in vivo predictive is essential to identify optimally performing formulations early in development. For ASDs containing an enteric polymer, consideration of buffer properties is essential. Herein, release rates of hydroxypropyl methyl cellulose acetate succinate (HPMCAS) and ritonavir from ASDs with a 20% drug loading were compared in phosphate and bicarbonate buffers with different molarities, at pH 6.5. The bioaccessibility of ritonavir from the ASD in the tiny-TIM apparatus was also evaluated and compared to that of the crystalline drug. The surface pH at the dissolving solid: solution interface was evaluated using a pH-sensitive fluorescence probe for HPMCAS and ASD compacts in phosphate and bicarbonate buffers. Drug and polymer were found to release congruently in all buffer systems, indicating that the polymer controlled the drug release. Release was slowest in 10 mM bicarbonate buffer, and much faster in phosphate buffers with molarities typically used in release testing (20-50 mM). Release from the 10 mM bicarbonate buffer was matched in a 5 mM phosphate buffer. The surface pH of HPMCAS and HPMCAS:ritonavir ASDs was found to be lower than the bulk solution pH, where surface pH differences largely explained release rate differences seen in the different buffer systems. Ritonavir was highly bioaccessible from the ASD, as assessed by the tiny-TIM system, and much less bioaccessible when crystalline drug was used. The observations highlight the need for continued development of biorelevant assays tailored for ASD formulation assessment.

Dexamethasone nanocrystals-embedded hydroxypropyl methylcellulose hydrogel increases cochlear delivery and attenuates hearing loss following intratympanic injection

Herein, dexamethasone (DEX) nanocrystalline suspension (NS)-embedded hydrogel (NS-G) was constructed using a hydroxypropyl methylcellulose (HPMC) polymer to enhance cochlear delivery and attenuate hearing loss following intratympanic (IT) injection. Hydrophobic steroidal nanocrystals were prepared using a bead milling technique and incorporated into a polysaccharide hydrogel. The NS-G system with HPMC (average molecular weight, 86,000 g/mol; 15 mg/mL) was characterized as follows: rod-shaped drug crystalline; particle size <300 nm; and constant complex viscosity ≤1.17 Pa·s. Pulverization of the drug particles into submicron diameters enhanced drug dissolution, while the HPMC matrix increased the residence time in the middle ear cavity, exhibiting a controlled release profile. The IT NS-G system elicited markedly enhanced and prolonged drug delivery (> 9 h) to the cochlear tissue compared with that of DEX sodium phosphate (DEX-SP), a water-soluble prodrug. In mice with kanamycin- and furosemide-induced ototoxicity, NS-G markedly enhanced hearing preservation across all frequencies (8–32 kHz), as revealed by an auditory brainstem response test, compared with both saline and DEX-SP. Moreover, treatment with NS-G showed enhanced anti-inflammatory effects, as evidenced by decreased levels of inflammation-related cytokines. Therefore, the IT administration of DEX NS-loaded HPMC hydrogels is a promising strategy for treating hearing loss.

Rheological properties of microfibrillated cellulose and hydroxypropyl methylcellulose blends in ethanol/water solvent systems

Rheological properties of microfibrillated cellulose and hydroxypropyl methylcellulose blends in ethanol/water solvent systems

Rheological and osteogenic effect of Agaricus blazei Murill polysaccharides on composite hydrogels based on HPMC/graphene oxide – A preliminary study

This study aimed to prepare and preliminarily characterize the potential bone restorative effect of composite hydrogels based on hydroxypropylmethylcellulose (HPMC), graphene oxide (GO), and polysaccharides from Agaricus blazei Murill mushroom (PAb). The chemical composition and morphology of the biomaterials were analyzed using FTIR, XRD, SEM, and EDS. Rheological tests were conducted on the hydrogels to assess their flow properties for in vivo application and product stability. Cytotoxicity assays were performed using the GO (1 – 100 µg mL–1) against human neutrophils. Additionally, an in vivo tooth extraction test was carried out by applying HPMC hydrogels containing GO and PAb directly into the alveoli to enhance oral bone restoration. The rheological behavior of the hydrogels followed the Ostwald de Waele model (R² > 0.99), with flow index (n) values below 1.0, indicating a pseudoplastic behavior. Furthermore, the consistency index (k) values increased with the addition of GO and PAb, suggesting a more complex structure, and altered flow behavior at lower shear rates. In the MTT assay, GO exhibited low cytotoxicity towards human neutrophils, maintaining cell viability above 95.0 % even at high concentrations. For the in vivo study, a bisphosphonate-induced osteonecrosis model was used to assess bone tissue healing through macroscopic and radiographic analyses. A significant improvement was observed in the reduction of bone tissue loss in rats treated with the hydrogels compared to the negative control (ZA group). These findings indicate that composite hydrogels containing HMPC/GO/PAb have the potential to be used as biomaterials for mitigating bone loss.

Enhancing the Biodegradability, Water Solubility, and Thermal Properties of Polyvinyl Alcohol through Natural Polymer Blending: An Approach toward Sustainable Polymer Applications.

The escalating environmental crisis posed by single-use plastics underscores the urgent need for sustainable alternatives. This study provides an approach to introduce biodegradable polymer blends by blending synthetic polyvinyl alcohol (PVA) with natural polymers-corn starch (CS) and hydroxypropyl methylcellulose (HPMC)-to address this challenge. Through a comprehensive analysis, including of the structure, mechanical strength, water solubility, biodegradability, and thermal properties, we investigated the enhanced performance of PVA-CS and PVA-HPMC blends over conventional polymers. Scanning electron microscopy (SEM) findings of pure PVA and its blends were studied, and we found a complete homogeneity between the PVA and both types of natural polymers in the case of a high concentration of PVA, whereas at lower concentration of PVA, some granules of CS and HMPC appear in the SEM. Blending corn starch (CS) with PVA significantly boosts its biodegradability in soil environments, since adding starch of 50 w/w duplicates the rate of PVA biodegradation. Incorporating hydroxypropyl methylcellulose (HPMC) with PVA not only improves water solubility but also enhances biodegradation rates, as the addition of HPMC increases the biodegradation of pure PVA from 10 to 100% and raises the water solubility from 80 to 100%, highlighting the significant acceleration of the biodegradation process and water solubility caused by HPMC addition, making these blends suitable for a wide range of applications, from packaging and agricultural films to biomedical engineering. The thermal properties of pure PVA and its blends with natural were studied using diffraction scanning calorimetry (DSC). It is found that the glass transition temperature (Tg) increases after adding natural polymers to PVA, referring to an improvement in the molecular weight and intermolecular interactions between blend molecules. Moreover, the amorphous structure of natural polymers makes the melting temperature ™ lessen after adding natural polymer, so the blends require lower temperature to remelt and be recycled again. For the mechanical properties, both types of natural polymer decrease the tensile strength and elongation at break, which overall weakens the mechanical properties of PVA. Our findings offer a promising pathway for the development of environmentally friendly polymers that do not compromise on performance, marking a significant step forward in polymer science's contribution to sustainability. This work presents detailed experimental and theoretical insights into novel polymerization methods and the utilization of biological strategies for advanced material design.

Formulation development of thermoresponsive quercetin nanoemulgels and in vitro investigation of their inhibitory activity on vascular endothelial growth factor-A inducing neovascularization from the retinal pigment epithelial cells

Quercetin is one of natural flavonoids. It has ability to hinder neovascularization in cancers by reducing activities of the vascular endothelial growth factor-A (VEGF-A). Regarding this particular activity, quercetin thus has a potential for managing the vasoproliferative retinopathies. Unfortunately, its hydrophobicity resulted in poor ocular bioavailability. A suitable intravitreal formulation should be developed to overcome this problem. This study was conducted to optimize formulations of thermoresponsive quercetin nanoemulgels (T-QNE-Gs) for intravitreal injection and to examine their in vitro for their inhibitory activity on VEGF-A inducing neovascularization from the retinal pigment endothelial cells. T-QNE-Gs were prepared by incorporation of gels consisting of various ratios of Pluronic F127 (F127) to Pluronic F68 (F68), with a fixed concentration of hydroxypropyl methylcellulose, into a quercetin nanoemulsion concentrate. The optimum formulation of T-QNE-Gs was 2F127–1F68 containing F127 and F68 at a 2:1 ratio. After sterilization, S–2F127–1F68 was obtained. The S–2F127–1F68 could flow properly at a room temperature (27 ± 1 °C) and became gel at a temperature of the posterior eye segment (35 ± 1 °C). It effectively inhibited migration and tube formation of the human umbilical vein endothelial cells and suppressed the VEGF-A gene expression and VEGF-A protein levels in the arising retinal pigment epithelial cells under a hypoxic condition. Therefore, S–2F127–1F68 had a potential for treatment of the vassoproliferative retinopathies and can be used for further investigation in animal models.