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Cancer has remained one of the leading causes of death worldwide, with a lack of effective treatment. The intrinsic shortcomings of conventional therapeutics regarding tumor specificity and non-specific toxicity prompt us to look for alternative therapeutics to mitigate these limitations. In this regard, we developed multifunctional bimetallic (FeCo) bi-MIL-88B-FC MOFs modified with folic acid--conjugated chitosan (FC) as drug delivery systems (DDS) for targeted delivery of 5-Fluorouracil (5-FU). The bi-MIL-88B nanocarriers were characterized through various techniques, including powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray, thermogravimetric analysis, and Fourier transform infrared spectroscopy. Interestingly, 5-FU@bi-MIL-88B-FC showed slower release of 5-FU due to a gated effect phenomenon endowed by FC surface coating compared to un-modified 5-FU@bi-MIL-88B. The pH-responsive drug release was observed, with 58% of the loaded 5-FU released in cancer cells mimicking pH (5.2) compared to only 24.9% released under physiological pH (5.4). The in vitro cytotoxicity and cellular internalization experiments revealed the superiority of 5-FU@bi-MIL-88B-FC as a highly potent targeted DDS against folate receptor (FR) positive SW480 cancer cells. Moreover, due to the presence of Fe and Co in the structure, bi-MIL-88B exhibited peroxidase-like activity for chemodynamic therapy. Based on the results, 5-FU@bi-MIL-88B-FC could serve as promising candidate for smart DDS by sustained drug release and selective targeting. [ABSTRACT FROM AUTHOR]

Membrane technology has recently been given extensive consideration for the treatment of effluent to remove suspended solids, organic compounds and inorganic contaminants such as heavy metals. The aim of this study was to prepare, characterize, and test membranes made of silk fibroin (SF) and polymethyl methacrylate (PMMA) blend with different wt% ratios (5%, 10%, and 15%), respectively. The membranes were prepared by phase inversion scheme using water as non‐solvent. Fourier transform infrared spectroscopy (FTIR) was performed to find chemical interactions between polymer matrix and fibroin. The mechanical property of synthesized membranes was also carried out. The surface roughness, and finger‐like pore geometry developed by impregnation of fibroin filler in membrane matrix were depicted by atomic force microscopy (AFM) and scanning electron microscope (SEM), respectively. Surface porosity improved from 4.5% ± 1.9% to 30.0% ± 2.8%, water contact angle reduced from 68° ± 3.0° to 38° ± 1.2°, and highest pure water permeation value (31 L m−2 h−1) was obtained with the addition of fibroin loading. The membrane showed a greater affinity for Cr(VI) in comparison with Pb(II). The highest % rejection was evaluated to be 83% and 56% for Cr(VI), and Pb(II) by utilizing 1.70 wt% fibroin filler in membrane composition, respectively. [ABSTRACT FROM AUTHOR]

The main objective of the current research work was to fabricate polyethylene glycol-based hydrogels for the controlled delivery of Ketorolac. Polyethylene glycol was chemically cross-linked with acrylic acid using 2-hydroxyethyl methacrylate as a cross-linker with ammonium persulfate and sodium metabisulphite as initiators. To determine the efficiency of the synthesized system, it was subjected to various structural characterization, such as Fourier transform infrared spectroscopy, Differential scanning calorimetry, Thermogravimetric analysis, and Scanning electron microscopy. All the results obtained from structural characterizations confirmed a well-cross-linked, thermally stable, and a porous system. Swelling and in-vitro release studies performed in pH 1.2 and 7.4 showed pH responsiveness as more swelling and drug release were observed in pH 7.4 as compared to pH 1.2. The drug release was considered as non-Fickian transport from kinetic modeling and partially controlled by the viscoelastic relaxation of hydrogel. Sol-gel fraction depicted that gel content was increased as the concentrations of the polymer, monomer, and cross linker were increased. Similarly, the results obtained from stability studies confirmed a stable synthesized system. Moreover, statistical analysis was also employed for a better comparison of the swelling and in-vitro results. [ABSTRACT FROM AUTHOR]

The aim of the current investigation was based on the development of pH-responsive hydrogels of chondroitin sulfate, carbopol, and polyvinyl alcohol polymerized with acrylic acid in the presence of ammonium persulfate and ethylene glycol dimethylacrylate for controlled drug delivery. A free radical polymerization technique was used for the preparation of these pH-responsive hydrogels. The gel fraction of the prepared hydrogels was increased with the increase in the chondroitin sulfate, carbopol, polyvinyl alcohol, and acrylic acid content, while the sol-fraction was decreased. Swelling and drug release studies were performed in various pH conditions. Greater swelling and drug release were observed at high pH values (pH 4.6 and 7.4) as compared to low pH value (pH 1.2), representing the pH-responsive nature of the synthesized hydrogels. Porosity and drug loading were increased with the incorporation of high concentrations of hydrogel contents except polyvinyl alcohol, which showed reverse effects. Similarly, biodegradation study reported a slow degradation rate of the prepared hydrogels with the increase in hydrogel constituents. Cytotoxicity study proved the safe use of developed hydrogels as no toxic effect was shown on T84 human colon cancer cells. Similarly, various characterizations, including Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy, were performed for prepared hydrogels. Hence, we could demonstrate that the prepared hydrogels can be used as a promising drug carrier for the controlled delivery of drugs. [ABSTRACT FROM AUTHOR]

Purpose of the current research work was to synthesize gelatin based hydrogels for the controlled release of salbutamol sulphate. Free radical polymerization technique was used for the synthesis of hydrogels. Gelatin was cross-linked chemically with monomer methacrylic acid using methylene bisacrylamide as cross-linker while ammonium persulphate and sodium metabisulphite were used as initiators. All the formulations were evaluated through Fourier transform infrared spectroscopy, differential scanning calorimetry, thermo gravimetric analysis and scanning electron microscopy. Swelling properties of formulated hydrogels were also evaluated in both pH 7.4 and 1.2. For drug release study, USP peddle method was used and release study was carried out in both pH 7.4 and 1.2. Fourier transform infrared spectroscopy confirmed that drug salbutamol sulphate is compatible with the formulated system. Moreover, thermal stability was also confirmed by TG/DSC studies providing the fact that thermal stability of the formulated hydrogels is high as compared to individual content. Sol–gel fraction confirmed that gel content increased as the concentrations of the polymer, monomer and cross-inker were increased. All formulations showed profound gel fraction. Similarly, pH dependent swelling was observed, experiencing higher swelling at higher pH as compared to lower pH. Toxicity study was also conducted which endorsed the safety of the hydrogels as no toxic effect was observed on vital organs. [ABSTRACT FROM AUTHOR]

The present study aimed to develop a stable interconnected matrix as a sustained release drug delivery material. Arabinoxylan (AX) was extracted from ispaghula husk and then crosslinked with different concentrations, i.e., 0.5, 1.0, and 1.5 g of CaCl2 per 0.25 g of AX. The crosslinking was confirmed through Fourier transform infrared spectroscopy. The swelling capacity of crosslinked AX (CL-AX) was evaluated against buffer solutions of pH 1.2, 6.8, 7.4, and water. The swelling capacity increased from pH 1.2 to pH 7.4 and followed the second order swelling kinetics. The swelling study also revealed that CL-AX with 1.0 g CaCl2 showed maximum swelling capacity. The swelling–deswelling (on–off switching) behavior of CL-AX was evaluated in water–ethanol, water–0.9% NaCl solution, and buffer solutions of pH 7.4–1.2 and showed responsive swelling–deswelling behavior. Scanning electron microscopy revealed a highly porous nature of CL-AX with a mesh of thin fibrous networking. Hemocompatibility studies of CL-AX revealed its non-thrombogenic and nonhemolytic attributes. The CL-AX matrix tablet prolonged the release of enalapril maleate for 24 h, and the drug release followed the zero order kinetics and super case-II transport mechanism. Therefore, CL-AX can be recognized as a stimuli responsive and hemocompatible biomaterial with sustained drug release potential. [ABSTRACT FROM AUTHOR]

In current research study, novel chitosan-based hydrogel was formulated via crosslinking graft copolymerization of acrylic acid (AA) and chitosan. Potassium persulfate was used as free radical generator in the presence of crosslinker (methylene bis acrylamide (MBA)). FTIR spectroscopy was employed to elucidate structure of hydrogel. Moreover, sample morphology was examined by scanning electron microscopy (SEM) and thermal analysis was conducted by using thermogravimetric analysis (DSC/TGA). The influence of reaction variables such as concentration of chitosan (CS), acrylic acid (AA) and MBA was optimized to attain hydrogel with significant swelling capacity. Chitosan-g-AA hydrogel depicted pH responsive attributes and swelling–deswelling pulsatile behavior was recorded at pHs 1.2 and 7.4. This on–off switching makes hydrogel ideal candidate for controlled drug delivery. [ABSTRACT FROM AUTHOR]

The major objective of this study is to fabricate a very promising system by loading anticancer agent in it which could be given to the cancer patients by oral administration and additionally that will liberate drugs in large intestine (affected/cancerous area). Minimum or no exposure of chemotherapeutic agents to gastric/small intestine will significantly eliminate the problem of adverse drug reactions. Cancer patients are facing severe problem of side/adverse effects due to intravenous colorectal carcinoma chemotherapy. So, an oral drug delivery system is designed to substitute the intravenous drug therapy. This study reports the synthesis of hybrid polymeric polyethylene glycol hydrogels (PEGA 4000) based on acrylic acid (AA), ammonium peroxodisulfate and ethylene glycol dimethacrylate (EGDMA) by solution polymerization method. PEGA 4000 hydrogels were used for colon targeting of hydrophilic anti-carcinoma drug (oxaliplatin). Development of new structure was confirmed by Fourier transform infrared spectroscopy. Surface morphology of developed hydrogel slabs was examined by scanning electron microscopy. Thermal gravimetric analysis of hydrogels revealed that there was an increase in thermal stability of PEGA 4000 hydrogels. Swelling study was performed in acidic and basic pH medium provided important information on drug release characteristics of hydrogels. The release of oxaliplatin (OXP) was significantly retarded at pH 1.2, while rapid release was observed at pH 7.4. The release rate of OXP increased with increasing concentration of PEG 4000 and AA. However, extent of drug release was significantly reduced on increasing concentration of EGDMA. Mechanism of release has been evaluated by applying various mathematical kinetic models. The tensile mechanical strength and elongation at break were also observed on different formulations based on various ratios of reaction contents. The consequents of our study suggest that fabricated PEGA 4000 hydrogels could serve as suitable target release delivery system and toxicity study endorsed biocompatibility of hydrogels to biological system. [ABSTRACT FROM AUTHOR]

Curcumin has been reported to be used widely against many types of pathological conditions in clinics. However, due to its limitations such as poor solubility, poor oral absorption and low stability have limited its applications. In the current study, a series of novel chemically cross-linkable depot gel formulations were developed based on thermoresponsive micellar polymer (Pluronic®127) with polyelectrolyte hydrophilic monomer, that is, 2-acrylamido-2-methylpropane sulfonic acid by cold and in situ grafting polymerization method. The formulations were aimed to deliver curcumin at controlled rate from in situ formed depot after administration through subcutaneous route in vivo. The sol-gel phase transitions of formulations were observed by rheological analysis, tube titling and optical transmittance measurements. Maximum swelling of gel formulations was observed at pH 7.4 and below CGT, that is, 25 °C. The in vitro release profile exhibits maximum drug release at pH 7.4 and 25 °C owing to relaxed gel state. In vitro degradation profile of gel formulations showed controlled degradation rate. Cell growth inhibition study confirmed the biocompatibility and safe nature of bare gel formulations against L929 cell lines. In vitro cytotoxic study showed that curcumin loaded in gel formulation has controlled pharmacological activity against HeLa and MCF-7 cancer cells as compared to free drug solution. The IC50 values calculated for pure curcumin solution (30 ± 0.77 µg/ml for HeLa and 27 ± 0.39 µg/ml for MCF-7) were found higher in comparison to curcumin-loaded thermogels against HeLa (19 ± 0.28 µg/ml and 23 ± 0.81 µg/ml) and MCF-7 (22 ± 0.54 µg/ml and 21 ± 0.49 µg/ml). Histopathological and hematological analysis showed the biocompatible nature of hydrogels. Structural confirmation was done by Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance spectroscopy (1H NMR). Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) confirmed the thermal stability of the gel formulation. The porous structure of gel formulations was assessed by scanning electron microscopic (SEM) analysis. Results concluded that newly developed gel formulations have thermoresponsive behavior with phase transition at body temperature and can be used as in situ controlled drug depot. [ABSTRACT FROM AUTHOR]

NiO nanostructure was synthesized using a simple co-precipitation method and was embedded on reduced graphene oxide surface via ultrasonication. Structural investigations were made through X-ray diffraction (XRD) and functional groups were confirmed by Fourier transform infrared spectroscopy (FTIR). XRD analysis revealed the grain size reduction with doping. Fourier transform infrared spectroscopy confirmed the presence of metal-oxygen bond in pristine and doped NiO nanostructure as well as the presence of carbon containing groups. Scanning electron microscopy (SEM) indicated that the particle size decreased when NiO nanostructure was doped with copper. BET surface area was found to increase almost up to 43 m2/g for Cu doped NiO nanostructure/rGO composite. Current-voltage measurements were performed using two probe method. UV–Visible spectroscopic profiles showed the blue and red shift for Cu doped NiO nanostructure and Cu doped NiO Nanostructure/rGO composite respectively. Rate constant for Cu doped NiO nanostructure/rGO composite found to increase 4.4 times than pristine NiO nanostructure. [ABSTRACT FROM AUTHOR]

Pectin-co-poly acrylic acid (Pec-co-poly (AA)) hydrogels are imperative and new type of chemically cross-linked hydrogels. A research was conducted to develop pH-sensitive, controlled release, and biocompatible hydrogels by free radical polymerization and scrutinize the suitability of Pec-co-poly (AA) hydrogels as drug carriers. Different formulations were designed using central composite model. N,N-Methylenebisacrylamide (MBA) was used as a cross-linker and benzoyl peroxide (BPO) as an initiator. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) showed that hydrogels are thermally stable. Hydrogels have a porous structure, clearly expressed by scanning electron microscopy (SEM). Fourier transform infrared spectroscopy (FTIR) results concede the grafting reaction of AA on pectin. Hydrogels were figured out for pH-responsive behaviour by dynamic and equilibrium swelling ratio at low and high pH. The effects of pectin and acrylic acid (AA) content on swelling were also studied and revealed an increasing trend in swelling with increasing concentration of either pectin or AA. Similarly, developed hydrogels were also evaluated for different modalities for drug loading and release employing nifedipine as model drug. Constructed models are found to be suitable prediction tools, with contour plots and response surface plots providing an easy tool for estimation of response nature over entire setting of variables. It is concluded that highly stable Pec-co-poly (AA) hydrogels are developed. These have potential to be used as carrier for controlled delivery of nifedipine. [ABSTRACT FROM AUTHOR]

Objectives: The study aimed to develop safe, effective, and targeted drug delivery system for administration of nonsteroidal anti-inflammatory drugs (NSAIDs) in the form of microgels. We developed pH responsive microgels to overcome the mucosal damage caused by traditional immediate release dosage forms. Colon targeting and controlled release formulations have the potential to improve efficacy and reduce undesirable effects associated with NSAIDs. Methods: The pH sensitive oral hydrogel demonstrates the potential to target the colon. Cellulose acetate phthalate (CAP) and hydroxyethyl methacrylate (HEMA) based microgel particles were produced using a free radical polymerization technique using ammonium persulfate (APS) initiator and methylenebisacrylamide (MBA) as the crosslinking agent. Swelling and in-vitro drug release studies were performed at a range of pH conditions. The produced formulations were characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy (SEM), and X-ray diffraction. Biocompatibility of the microgels was analyzed in cytotoxicity studies. Key findings: The swelling and release rate were negligible at pH 1.2, which confirmed the pH-responsiveness of CAP-co-poly(HEMA). The co-polymeric system prevents the release of ketoprofen sodium in the stomach owing to limited swelling at gastric pH, whilst promoting release at the basic pH observed in the colon. SEM images confirmed porous nature of the microgels that facilitate effective drug diffusion through the polymeric matrix. Cytotoxicity studies revealed biocompatibility of hydrogels. Conclusion: These investigations showed that that the controlled drug release and gastro-protective drug delivery of NSAIDS was achieved using CAP-co-poly(HEMA) microgel particles. [ABSTRACT FROM AUTHOR]

The present research work is focused on development and characterization of copolymerized pectin sulfonic acid hydrogels and to evaluate controlled delivery of captopril. Series of pectin–sulfonic acid-based hydrogels were synthesized by free radical copolymerization technique. Pectin has been chemically cross-linked with 2-acrylamido-2-methylpropane sulfonic acid in the presence of ammonium persulfate and sodium metabisulfite as redox initiator. Methylene bisacrylamide (MBA) was used as cross-linking agent in varying amount to investigate the degree of cross-linking as a function of increased concentration of polymer (pectin) and monomer (AMPS). Captopril was incorporated as model drug in formulated hydrogels. Fourier transform infrared spectroscopy (FTIR) was performed for structural analysis. In vitro swelling and release studies of captopril were carried out at both pH 1.2 and 7.4. Sol–gel fraction was also calculated to determine the amount of uncross-linked polymer fraction in prepared hydrogels. FTIR analysis confirmed the formation of cross-linked network between polymer (pectin) and monomer (AMPS). All formulations showed pH-dependent swelling behavior because of pectin, and drug release pattern was high at pH 1.2, and prolonged release was observed at pH 7.4 because of pH-independent behavior of sulfonic acid. The results of sol–gel analysis confirmed that gel fraction increases as amount of AMPS and MBA was increased. From current research study, it is concluded that stable formulations of pectin–sulfonic acid were formed by optimized copolymerization reaction. This newly developed polymeric network could serve as a potential system for controlled delivery of captopril for prolonged period. [ABSTRACT FROM AUTHOR]

This study was aimed to develop chemically cross‐linked matrix system of polycaprolactone‐co‐poly (methacrylic acid) through free radical polymerization method for controlled delivery of highly water‐soluble drug venlafaxine HCl. A hydrophobic polymer, polycaprolactone has been cross‐linked chemically with methacrylic acid by ethylene glycol dimethacrylate (EGDMA) as cross‐linking agent, and benzoyl peroxide was added as reaction initiator. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), and sol‐gel fraction were performed for characterization and structural analysis of polymeric system. Different feed ratios of polycaprolactone, methacrylic acid, and EGDMA were incorporated to investigate the effect of polymer, monomer, and degree of cross‐linking on swelling behavior and release pattern of model drug. pH‐responsive nature of hydrogel was evaluated at low and high pH. FTIR, TGA, and DSC confirmed the formation of new cross‐linked network. pH sensitivity of hydrogel is revealed by increased swelling at pH 7.4. Toxicity study was also performed on rabbits to evaluate cytotoxicity and biocompatibility of developed formulation. Polycaprolactone hydrogels showed low swelling with increased polymer and cross‐linker concentration while swelling increased with high concentration of monomer. Swelling controlled in vitro drug release was found in hydrogels. Gel contents were increased with increase in ratio of polymer, monomer, and cross‐linking agent. Toxicity study endorsed that developed hydrogels were nontoxic and biocompatible. [ABSTRACT FROM AUTHOR]

ABSTRACT Solubility of poorly water-soluble drugs is one of the most emerging issue associated with these drugs to form a suitable dosage form that will provide desired pharmacological response. Their low solubility causes elimination of most of the drug from body as such, and desired therapeutic levels are not achieved. Polymers are major players in these formulations, e.g., chitosan, polyvinyl pyrolidone, polyvinyl alcohol, β-cyclodextrin, etc. β-Cyclodextrin is one of the most efficient polymer among all of these to work as a carrier for these drugs to enhance solubility. In the present work, microparticles were prepared by different techniques to enhance solubility of rosuvastatin calcium. Microparticles were evaluated for Fourier transform infrared spectroscopy (FTIR), thermal analysis, dissolution studies, powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and stability studies to confirm enhancement in solubility. Different in vitro kinetic models such as zero order, first order, Higuchi, and Korsmeyer-Peppas were applied to determine the release behavior of drug from prepared formulations. Results were statistically analyzed by the one-way ANOVA test, and the p value was determined to check significant results. Results of PXRD had shown that drug nature was changed from crystalline to amorphous, and FTIR and thermal analysis confirmed that the complex was formed between drug and β-cyclodextrin. SEM images had shown that microparticles had small size loaded with drug. Results had shown that formulation F3 prepared by solid dispersion of drug and β-cyclodextrin in 1:3 had achieved maximum release of drug 97% within 45 min. [ABSTRACT FROM AUTHOR]

Objective of the study was to synthesize a chemically cross-linked poly(hydroxyethylmethacrylate-co-methacrylic acid) hydrogel [p(HEMA-co-MAA hydrogel)] for pH-responsive, controlled drug delivery of Flurbiprofen. pH-sensitive hydrogel drug delivery system was synthesized with the help of poly hydroxyethyl methacrylate (HEMA) and methacrylic acid (MAA) by using ethylene glycol dimethacrylate (EGDMA) as crosslinker. The monomers (HEMA and MAA) were successfully cross linked through free radical polymerization process, initiated by benzoyl peroxide in an aqueous medium. All formulations were loaded with Flurbiprofen as a model drug and evaluated at pH 1.2 and pH 7.4 to investigate pH-responsive nature of the system. Fourier transform infrared spectroscopy (FTIR) was performed to confirm the cross-linking of copolymer while thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) were performed to evaluate the thermal stability of the system. Swelling studies and in-vitro release studies were carried out to evaluate pH-responsive nature of the hydrogels. FTIR confirmed that monomers were successfully cross-linked to form a copolymer. Hydrogel system showed less swelling at lower pH while at higher pH, it showed higher swelling, releasing drug in the same fashion. It was concluded that a stable hydrogel network was chemically cross-linked showing pH-responsive nature and thus, synthesized p(HEMA-co-MAA) hydrogels can be successfully employed as potential candidate for controlled drug delivery. [ABSTRACT FROM AUTHOR]

Due to the current COVID-19 pandemic, there is a crucial need for the development of antimicrobial and antiviral personal protective equipment such as facemasks and gowns. Therefore, in this research we fabricated electrospun nanofibers composite with polyvinyl alcohol, aloe vera, and zinc oxide nanoparticles for end application in medical devices. Electrospun nanofibers were made with varying concentrations of aloe vera (1%, 2%, 3%, 4%) having a constant concentration of ZnO (0.5%) with varying concentrations of ZnO nanoparticles (1%, 2%, 3%, 4%) having a constant concentration of aloe vera (0.5%). To check the morphology and composition, all prepared nanofibers were subjected to different characterization techniques, such as Scanning Electron Microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FTIR). In addition, its antimicrobial activity was checked both with qualitative and quantitative approaches against gram-positive (Staphylococcus aureus) bacteria and gram-negative (Escherichia coli) bacteria. The results suggest that increasing ZnO concentration kills and inhibits bacterial growth more proficiently compared to increasing aloe vera concentration in electrospun nanofibers; the highest antimicrobial was found with 4% ZnO, killing almost 100% of gram-positive (Staphylococcus aureus) bacteria and 99.2% of gram-negative (Escherichia coli) bacteria. These fabricated nanofibers have potential applications in medical devices and would help control the spread of many diseases. [ABSTRACT FROM AUTHOR]

In the perspective of fossil fuel depletion, the importance of renewable and substitute fuels is remarkable. In this study, clean liquid-fuel was obtained from tar through catalytic hydrorefining method. Hydrorefining catalysts were prepared by impregnation, containing tungsten-nickel (W-Ni), molybdenum-nickel (Mo-Ni), tungsten-molybdenum-nickel (W-Mo-Ni), and tungsten-molybdenum-cobalt (W-Mo-Co). γ-alumina was used as catalysts supporter. The clean liquid fuel product was analyzed by Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry, elemental analyzer, octane number for gasoline fraction and cetane-number for diesel fraction, and Engler distillation range. The rules of sulfur and nitrogen content were also investigated. The overall product yield was up to 97%, and the sulfur and nitrogen content was less than 70 ppm. The W-Mo-Ni/γ-Al2O3 catalyst showed high performance in catalytic hydrofinishing and good stabilization under required conditions. [ABSTRACT FROM AUTHOR]

Aminosilane grafted and diamine modifiedreactive montmorillonitewas exploited to generate aromatic polyamide based nanocomposites.For better compatibility, the hydrophilic nature of montmorillonitewas changed into organophilic using 1,4-phenylenediamine, and thehydroxyl groups present on the clay surface and edges were used tograft 3-aminopropyltriethoxysilane (APTS) on clay sheets. The dispersionof clay was monitored in the polyamide obtained from 1,4-phenylenediamine,4,4′-oxydianiline, and isophthaloyl chloride. These chainswere converted into carbonyl chloride ends to interact with free aminegroups of grafted APTS and diamine. Thin films were probed for FTIR,XRD, SEM, TEM, tensile testing, TGA, and DSC measurements. The resultsdescribed ample dispersion of clay in the nanocomposites with tensilestrength increased 110% and elongation increased 172% upon the additionof 4–6 wt % clay. Thermal decomposition temperatures of thenanocomposites were in the range 425–480 °C. The glasstransition temperature increased up to 142.4 °C with 6 wt % additionof organoclay. [ABSTRACT FROM AUTHOR]

Abstract: A single unit catalyst system (Pt/silica–chiral modifier) is developed for the enantioselective hydrogenation of ethyl pyruvate. Cinchonidine was tethered directly without prior modification over carboxylate functionalized SBA-15 by the reaction of vinyl group in cinchonidine with –COOH group in functionalized SBA-15 through ester linkage. Then Pt nanoparticles were deposited over cinchonidine tethered SBA-15. The mesostructures were characterized by small-angle XRD, N2 sorption and TEM, while the surface functionalization was confirmed by FTIR, TG/DTA and solid state 13C NMR. Enantioselectivity of the catalyst system for hydrogenation of ethyl pyruvate was determined by GC/FID. The highest enantiomeric excess was achieved as 70.8% and the catalyst recyclability was authenticated even after 3rd reuse without significant loss in enantiomeric excess. [Copyright &y& Elsevier]

In the current research work, palladium (Pd) nanoparticles were electrochemically deposited on a nitrogen doped montmorillonite (CNx-MMT) support using the underpotential deposition (UPD) method. The prepared Pd based composite electrode was studied as an electrocatalyst for methanol fuel oxidation. The catalysts and the supporting materials montmorillonite, acid activated montmorillonite, and nitrogen doped montmorillonite (MMT, HMMT and CNx-HMMT) were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) and electrochemical characterization by cyclic voltammetry (CV). The results indicated that Pd supported on CNx-HMMT possesses enhanced electrocatalytic activity and stability compared to commercial Pd/C, which was attributed to its higher electrochemical surface area (ECSA) (23.00 m2 g−1). The results demonstrated the potential application of novel Pd/CNx-HMMT composite nanomaterial as electrocatalysts for methanol electrooxidation in direct methanol fuel cells (DMFCs). [ABSTRACT FROM AUTHOR]

The objective of the current study work was to fabricate sodium poly(styrene sulfonate-co-poly acrylic acid) (SPSPAA) hydrogels by using a free radical co-polymerization method for controlled delivery of ketorolac tromethamine (KT). Polymer (sodium poly(styrene sulfonate) (SPS) polymerized with monomer acrylic acid (AA) in the presence of initiator ammonium peroxodisulfate (APS) and cross-linker N′,N′-Methylene bisacrylamide (MBA). Different combinations of polymer, cross-linker and monomer, were employed for development of polymeric hydrogels. Various studies such as sol-gel, drug loading, dynamic swelling, and drug release studies were carried out to know the sol and gel portion of SPSPAA, swelling behavior of hydrogels at different pH media (1.2 and 7.4), quantification of drug loaded by fabricated hydrogels, and amount release of KT at pH 1.2 and 7.4. Higher dynamic swelling was found at pH 7.4 compared to pH 1.2, and as a result, greater percent release of drug was perceived at pH 7.4. Thermal stability, crystallinity, confirmation of functional groups and development of a new polymeric system, and surface morphology were evaluated via Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Powder X-ray Diffraction (PXRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) respectively. The results showed that the present work could be used as a potential candidate for controlled delivery of KT. [ABSTRACT FROM AUTHOR]

The poplar biochar (PB) was prepared at different pyrolysis temperatures and the hot pressing method was applied to prepare composites with PB based on high-density polyethylene (HDPE). The effects of pyrolysis temperature on the characterizations of PB were analyzed and the PB/HDPE composites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Differential scanning calorimetry (DSC), Scanning electron microscope (SEM), and their mechanical properties. The results showed that the specific surface area and pore volume increased, polar functional groups and the polarity of PB decreased with the increase of pyrolysis temperatures. Moreover, the addition of PB had no effect on the microcrystalline structure but the intensity of the peaks of PB/HDPE composites was reduced. FTIR analysis of PB/HDPE composites showed no new functional groups which indicated that PB and HDPE did not react chemically with each other. Besides, the addition of PB did not change the melting temperature of HDPE but it promoted the early crystallization of PB/HDPE composites. The mechanical analysis showed that the flexural strength improved and the impact strength decreased of PB/HDPE composites by the addition of PB. Image 1 • The poplar biochar (PB) prepared at 600 °C has the most significant pore characteristics and least polar functional groups. • PB/high-density polyethylene (HDPE) composites were prepared through the process of hot pressing. • The addition of PB had an important influence on the basic characterization of PB/HDPE composites. • The pores of PB allowed HDPE to flow in creating an interlocking and improving the mechanical properties. [ABSTRACT FROM AUTHOR]

Injectable hydrogel with multifunctional tunable properties comprising biocompatibility, anti-oxidative, anti-bacterial, and/or anti-infection are highly preferred to efficiently promote diabetic wound repair and its development remains a challenge. In this study, we report hyaluronic acid and Pullulan-based injectable hydrogel loaded with curcumin that could potentiate reepithelization, increase angiogenesis, and collagen deposition at wound microenvironment to endorse healing cascade compared to other treatment groups. The physical interaction and self-assembly of hyaluronic acid-Pullulan- grafted -pluronic F127 injectable hydrogel were confirmed using nuclear magnetic resonance (1H NMR) and Fourier transformed infrared spectroscopy (FT-IR), and cytocompatibility was confirmed by fibroblast viability assay. The CUR-laden hyaluronic acid-Pullulan- g -F127 injectable hydrogel promptly undergoes a sol-gel transition and has proved to potentiate wound healing in a streptozotocin-induced diabetic rat model by promoting 93% of wound closure compared to other groups having 35%, 38%, and 62%. The comparative in vivo study and histological examination was conducted which demonstrated an expeditious recovery rate by significantly reducing the wound healing days i.e. 35 days in a control group, 33 days in the CUR suspension group, 21 days in unloaded injectable, and 13 days was observed in CUR loaded hydrogel group. Furthermore, we suggest that the injectable hydrogel laden with CUR showed a prompt wound healing potential by increasing the cell proliferation and serves as a drug delivery platform for sustained and targeted delivery of hydrophobic moieties. Graphical illustration of the developmental process of HA-Pu-based-F127 hydrogel for diabetic wound healing, indicating sol-gel phase transition at physiological temperature and porous structure. The wound tissue regeneration after subcutaneous administration along with granulation tissue formation in the wound healing cascade. [Display omitted] [ABSTRACT FROM AUTHOR]

Wounds are often recalcitrant to traditional wound dressings and a bioactive and biodegradable wound dressing using hydrogel membranes can be a promising approach for wound healing applications. The present research aimed to design hydrogel membranes based on hyaluronic acid, pullulan and polyvinyl alcohol and loaded with chitosan based cefepime nanoparticles for potential use in cutaneous wound healing. The developed membranes were evaluated using dynamic light scattering, proton nuclear magnetic resonance, Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. The results indicated the novel crosslinking and thermal stability of the fabricated hydrogel membrane. The in vitro analysis demonstrates that the developed membrane has water vapors transmission rate (WVTR) between 2000 and 2500 g/m2/day and oxygen permeability between 7 and 14 mg/L, which lies in the range of an ideal dressing. The swelling capacity and surface porosity to liberate encapsulated drug (cefepime) in a sustained manner and 88% of drug release was observed. The cefepime loaded hydrogel membrane demonstrated a higher zone of inhibition against Staphylococcus aureus , Pseudomonas aeruginosa, and Escherichia coli and excisional rat model exhibit expeditious recovery rate. The developed hydrogel membrane loaded with cefepime nanoparticles is a promising approach for topical application and has greater potential for an accelerated wound healing process. Unlabelled Image [ABSTRACT FROM AUTHOR]

The aim of this study was to develop and characterize a pH sensitive, biodegradable, interpenetrating polymeric network (IPNs) for colon specific delivery of sulfasalazine in ulcerative colitis. It also entailed in-vitro and in-vivo evaluations to optimize colon targeting efficiency, improve drug accumulation at the target site, and ameliorate the off-target effects of chemotherapy. Pectin was grafted with polyethylene glycol (PEG) and methacrylic acid (MAA) by free radical polymerization. Fourier transformed infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), energy dispersion X-ray (EDX) and powder X-ray diffraction (XRD) results confirmed the development of stable pectin-g-(PEG-co-MAA) hydrogels. The swelling and release studies exhibited that the hydrogels were capable of releasing drug specifically at colonic pH (pH 7.4). The toxicological potential of polymers, monomers and hydrogel was investigated using the Balb/c animal model, that confirmed the safety of the hydrogels. In vitro degradation of the hydrogel was evaluated using pectinase enzyme in various simulated fluids and the results showed that the hydrogels were susceptible to biodegradation by the natural microflora of the colon. In-vivo study was performed using Dextran sulphate sodium (DSS) rat model proved the hydrogels to be effective in the management of UC. Unlabelled Image [ABSTRACT FROM AUTHOR]

The biopolymers-based two-fold system could provide a sustained release platform for drug delivery to the brain resisting the mucociliary clearance, enzymatic degradation, bypassing the first-pass hepatic metabolism, and BBB thus providing superior bioavailability through intranasal administration. In this study, poloxamers PF-127/PF-68 grafted chitosan HCl-co-guar gum-based thermoresponsive hydrogel loaded with eletriptan hydrobromide laden pullulan nanoparticles was synthesized and subjected to dynamic light scattering, Fourier transform infrared spectroscopy, thermal analysis, x-ray diffraction, scanning electron microscopy, stability studies, mucoadhesive strength and time, gel strength, cloud point assessment, rheological assessment, ex-vivo permeation, cell viability assay, histology studies, and in-vivo Pharmacokinetics studies, etc. It is quite evident that CSG-EH-NPs T-Hgel has an enhanced sustained release drug profile where approximately 86 % and 84 % of drug released in phosphate buffer saline and simulated nasal fluid respectively throughout 48 h compared to EH-NPs where 99.44 % and 97.53 % of the drug was released in PBS and SNF for 8 h. In-vivo PKa parameters i.e., mean residence time (MRT) of 11.9 ± 0.83 compared to EH-NPs MRT of 10.2 ± 0.92 and area under the curve (AUC tot) of 42,540.5 ± 5314.14 comparing to AUC tot of EH-NPs 38,026 ± 6343.1 also establish the superiority of CSG-EH-NPs T-Hgel. [Display omitted] • Bio polymers-based EH-NPs laden thermoresponsive hydrogels were developed and evaluated both in vitro and in vivo. • CSG-EH-NPs T-Hgel based on chitosan HCl, guar gum have shown biocompatibility and non-toxicity. • CSG-EH-NPs T-Hgel has an optimum mucoadhession time and strength and could retain in the nasal cavity for a longer period. [ABSTRACT FROM AUTHOR]

Aim of the study was to enhance the solubility of Chlorthalidone by developing beta-cyclodextrin cross-linked hydrophilic nanomatrices. Nine different formulations were fabricated by free radical polymerization technique. All formulations were characterized through different studies. FTIR spectroscopy of unloaded and loaded nanomatrices was processed to determine compatibility of constituents and that of the drug with the system. Surface morphology of the nanomatrices was studied by SEM. The size of the optimized formulation was determined by zeta sizer. Swelling, in-vitro release and solubility studies were carried out in different media and results of in-vitro release profiles of nanomatrices and commercially available tablet of Chlorthalidone were compared. For determination of biocompatibility, toxicity studies were proclaimed in rabbits. Main peaks of corresponding functional groups of individual constituents and that of drug were depicted in FTIR spectra of unloaded and loaded nanomatrices. Porous and fluffy structure was visualized through SEM images. Particle size of the optimized formulation was in the range of 175 ± 5.27 nm. Percent loading of optimized formulation showed the best result. Comparing the in-vitro drug release profiles of nanomatrices and commercially available tablet, the results of the synthesized nanomatrices were quite satisfactory. Solubility profiles were also high as compared to the drug alone. Moreover, toxicity studies confirmed that nanomatrices were biocompatible and no sign of any toxic effect was found. We concluded that our developed nanomatrices had successfully enhanced the solubility of Chlorthalidone and can also be used for other poorly aqueous soluble drugs. Unlabelled Image [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Three novel ferrocene-substituted thiosemicarbazones were synthesized. • XRD, FT-IR, mass and UV–Vis were performed for the characterization. • Computational study was done for the comparative study. • Comparative study reveals a good agreement between experimental and DFT results. • Frontier molecular orbital and natural bond orbital analysis were performed using M06/6–31 + G(d,p) level. • Nonlinear optical properties were also calculated using M06/6–31 + G(d,p) level of theory. Abstract The thiosemicarbazones have exciting biological and nonlinear optical (NLO) applications. The present study reports detail experimental and computational studies of three novel ferrocene-substituted thiosemicarbazones: (E/Z)-4-benzyl-1-(1-ferrocenylethyl)thiosemicarbazones (1), (E/Z)-4-(4-chlorobenzyl)-1-(1-ferrocenyl-ethyl) thiosemicarbazone (2) and (E/Z)-4-(2-bromo benzyl)-1-(1-ferrocenylethyl)thiosemicarbazone (3). These compounds were synthesized and resolved into their single crystal structures for the estimation of unit cells, space groups, bond angles and bond lengths. Chemical structures of 1 – 3 were further characterized spectroscopically employing nuclear magnetic resonance technique (1H NMR), infrared (FT-IR), mass and UV–Visible studies. Computational studies of 1 – 3 were performed using density functional theory (DFT) tools at M06 level of theory and 6–31 + G(d,p) basis set combination to gain the optimized geometry. A good correlation was found between experimental SC-XRD structures and DFT optimized geometries. Electronic properties including natural bond orbital (NBO) analysis, frontier molecular orbitals (FMOs) analysis, spectroscopic FT-IR data and NLO properties were calculated using same M06/6–31 + G(d,p) level of theory. NBO analysis confirmed the formation of charge separation state due to successful migration of electrons from donor to acceptor unit through π-bridge. Global reactivity parameters were estimated using energies of FMOs which described that 1 – 3 are chemically hard and stable molecules. Vertical electronic transition states were calculated using time-dependent DFT (TDDFT) at same level of theory. NLO properties of 1 – 3 were computed 5.77, 3.48 and 8.93 times greater than the standard urea molecule respectively. Two-state model confirmed the potential of synthesized molecules as NLO candidates. [ABSTRACT FROM AUTHOR]

A greener, cleaner cement called geopolymer has recently been developed instead of Portland cement as a grouting material, with improved grout properties and reduced carbon dioxide emissions. Nevertheless, the investigation of geopolymer's rheological and viscoelastic characteristics is still inadequate for grouting materials. Therefore, in this paper, the rheological and viscoelastic properties of geopolymer grouting material (GGM) with different content of fly ash (FA), slag (SL), and silica fume (SF) are studied. It is concluded that for the shear stress with a fixed shear rate (100 s−1), using 20 %–30% SL to replace FA significantly partially increases the shear stress of FA-based GGM. Further use of 20 %–30% SF to partially replace SL reduces the shear stress of FA/SL-based GGM. The yield stress and plastic viscosity of GGM present similar trends with the shear stress. In contrast, the slump spread shows a change rule contrary to the above parameters. The static rheological behavior of all GGMs fits a Bingham model regardless of the time and mixture. An approximate linear decline of storage modulus (G′) was detected in the frequency sweep test, indicating the pseudoplastic dynamic rheological behavior of GGMs under the oscillatory shearing. The yield stresses of GGM with FA, SL, and SF are decreased over time under shearing load. These results signify that GGM with FA, SL, and SF can quickly recover good workability after retempering. SL and SF increase the G′ of GGM due to higher chemical adhesion and specific surface area, respectively, as evident from the amplitude sweep test. Using 20 %–30% SF to replace SL partially rose the peak G′ significantly and lowered the decline slopes of the G′ curve in the frequency sweep test. The fluctuation of G′ cure is also remitted considerably by the inclusion of SF. Calorimetric and Fourier Transform Infrared Spectroscopy (FTIR) tests revealed the quick generation of C-(A)-S-H, leading to the poor flowability of GGM with FA and SL. The rapid dissolution of SF increases the modulus of the activator and reduces the basicity of the activator, leading to the results of using SF to improve the flowability of GGM with FA and SL. The study indicates that geopolymer is suitable for using grouting material instead of Portland cement paste. Different combinations of FA, SL, and SF can be used to modify the flowability of GGM. [ABSTRACT FROM AUTHOR]