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Herein the present work, aloe vera (AV) and sterculia gum (SG) based polymer network hydrogels have been designed for use in wound dressing and drug delivery (DD) applications. The hydrogels were prepared by graft copolymerization reaction of poly(2-(methacryloyloxy) ethyl trimethylammonium chloride) [poly (METAC)] onto AV and SG. Polymers were characterized by FESEM, SEM, EDS, AFM, C13 NMR, FTIR, XRD and TGA-DTG analysis. Swelling, drug delivery and biomedical properties of dressings have been evaluated. Sustained diffusion of moxifloxacin drug from dressings exhibited a non-Fickian diffusion mechanism and the release profile was best fitted in the Korsmeyer-Peppas kinetic model. Various interactions of polymers with blood and goat membranes revealed the biocompatible and mucoadhesive nature of the dressings. Hydrogel dressings were found permeable to O2 and water vapour and impermeable to microbes. Overall, these properties revealed that these hydrogels could act as suitable materials for design of wound dressings. Furthermore, antioxidant properties of AV, wound healing characteristic of SG, antibacterial properties of poly(METAC) and encapsulated moxifloxacin drug in hydrogel dressings may enhance the wound healing potential of hydrogel wound dressings (HWD).

Keeping in view the progressive future prospectus of carbohydrate research, herein, the potential of bioactive polysaccharides aloe vera (AV) and sterculia gum (SG) was explored to develop network hydrogel wound dressings. Both polysaccharides, acemannan of AV gel and glucuronic-galacturonic acid of SG accelerate wound healing process. The antibiotic drug cefuroxime encapsulated dressings were designed by graft-copolymerization with carbopol. The copolymers were characterized by SEM, AFM, FTIR, C13 NMR, XRD, TGA-DTG, DSC and swelling studies. The slow diffusion of cefuroxime drug exhibited non-Fickian mechanism and release of drug was occurred with a first order kinetic model. Polymer-bio membrane interactions indicated mucoadhesion nature. The clot formation was reduced during polymer-blood interactions indicated bio-compatible nature of the dressings moreover dressings were found antioxidant in nature. The porous dressings were O2 permeable and microbial impermeable. The hydrogel dressings revealed antimicrobial activity against P. aeruginosa. Degree of antimicrobial activity enhanced in case of hydrogel wound dressings loaded with cefuroxime. Overall, the results of these biochemical assays, sustained release of antibiotic drug and inherent wound healing potential of AV-SG indicated the use of hydrogels as dressing materials for better wound healing.

Polysaccharides have been applied in food and biomedical applications. Bioactive dietary fiber sterculia gum (SG) has been used for treatment of diarrhea. Therefore, in present research, SG has been used for development of drug delivery (DD) system for controlled release of metronidazole to improve its pharmacotherapy for amoebic dysentery. Co-polymers were characterized by Cryo-scanning electron microscopy (Cryo-SEM), atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy, 13C nuclear magnetic resonance (NMR) spectroscopy,), X-ray diffraction (XRD), thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC). Haemolytic index values of grafted product was less than 5 percent and DPPH assay illustrated free radical scavenging of hydrogels and bigels 74.00 ± 0.003% and 47.00 ± 0.005% respectively. Mucoadhesion experiment demonstrated that both hydrogels and bigels exhibited adhesion with intestinal mucus membrane required 0.034 ± 0.004 and 0.037 ± 0.002 N detachment force during mucoadhesion test. Diffusion of metronidazole was slow in sustained manner with Fickian diffusion mechanism. Overall results revealed biocompatible, antioxidant, and mucoadhesive properties of sterculia gum based gels which may be useful for DD applications of gastrointestinal infections.

In present scenario, anthropogenic activities have degraded the quality of water bodies to an unbearable level. Discharge of untreated industrial and other effluents have made the water unconsumable. Present work is an attempt to fabricate new stimuli responsive adsorbent based on natural exudate gum sterculia, an indigenous natural gum for uptake of a cationic dye malachite green. Magnetic field responsive terculia gum-graft-poly(n-isopropylacrylamide-co-acrylamide) nanocomposite have been prepared and assessed it as adsorbents for enrichment of malachite green from aqueous solution. The nanocomposite is characterized by FTIR, TG-DTA, VSM and swelling studies. The VSM results have shown is superparamagnetic behaviour of nanocomposite with saturation magnetization of 1.5065 emu/g. The adsorption follows Temkin isotherm and results indicate maximum adsorption capacity of 19.977 (98.78%) malachite green. The desorption studies demonstrates excellent recovery ability of nanocomposite. The adsorption study confirms the prospective applications of polysaccharide based magnetic hydrogel for the fruitful and greener disposal of cationic dyes. [ABSTRACT FROM AUTHOR]

Introduction: Keeping in view the role of polysaccharide gums in pharmaceutical applications. Herein this research, Moringa gum (MOG) and Sterculia gum (SG) polysaccharides have been explored to design the network structure in the form of hydrogels which can act as a wound dressing for better wound healing. Both gums are hydrophilic stem exudate and their anti-fungal and antioxidant activities have been reported for wound healing which can help the increase in wound healing potential of the antibiotic drug encapsulated hydrogel dressings. Objectives: To design the moringa gum, sterculia gum and polyacrylic acid based hydrogel wound dressings by graft copolymerization method impregnated with antibiotic drug levofloxacin for better wound care. Methodology: The co-polymers were prepared by grafting and crosslinking of the polyacrylic acid onto MOG and SG. The copolymers were characterized by cryo-SEM, AFM, FTIR, 13C NMR and swelling studies along with the evaluation of blood compatibility, wound fluid absorption, antioxidant activity, permeability (O2, H2O and, microbial), mucoadhesion, mechanical and in vitro release dynamics of antibiotic drug levofloxacin. Results and conclusion: The Cryo-SEM and AFM images of the hydrogels showed the porous nature and rough surface morphology of the hydrogels. The porosity in the hydrogel controlled the wound fluid absorption and drug diffusion from dressing. The release of the levofloxacin from MOG-cl-SG-co-poly(AAc) hydrogel occurred by the non-Fickian diffusion mechanism and release profile was best fitted in the Korsmeyer-Peppas kinetic model of drug release in the simulated wound fluid . The gum-based dressings were found permeable and antioxidant in nature. Overall, these hydrogels could be proposed as suitable materials for biomedical applications including drug delivery and wound dressing for better wound care.

Constipation and associated health issues like acid reflux, malnutrition were commonly observed in regions with water availability limitations. Although some of the products available in the market address this issue, there is limited research on development of such products which will be able to solve multiple associated issues. Sterculia gum, a natural product known for water retention and associated properties in traditional systems of medicine. Despite this, research and therapeutic applications of this product are in infancy. This study was aimed to develop laxative oral granules of sterculia gum with some other therapeutically and nutraceutical active ingredients for multiple applications as bulk laxative, demulcent, water retention agent, diarrhea and appetite controller in the management of obesity. Sterculia gum, magnesium trisilicate, dried magnesium sulphate, heavy kaolin and excipients characterization and product development was carried out with developed in house formulation technology. Developed formulation was evaluated for various formulation based evaluation parameters. Desirable pH range of 4.3 to 6.9 was observed indicating reduction in acidic properties of sterculia gum; good swelling index was observed 240ml/3gm. Identification tests and assay of active ingredients were carried and found to be within specified limit range. Developed formulation showed desirable stability of 12 months indicating good shelf life of product. Study results revealed developed formulation can be further investigated in clinical studies and might be served as novel dosage form for therapeutic applications in habitual constipation for multiple therapeutic targets with single product. [ABSTRACT FROM AUTHOR]

Trees of the genus Sterculia produce polysaccharide-rich exudates, such as karaya gum (Sterculia urens), chicha gum (Sterculia striata), and Sterculia foetida gum. These anionic biomaterials are biodegradable, with high viscosity, low toxicity, and gelling properties in aqueous media. According to these properties, they show promising applications as a polymer matrix for use in drug delivery systems. For this application, both the chemically modified and the unmodified polysaccharide are used. This review focuses on analyzing the state of the art of recent studies on the use of Sterculia gums in a variety of pharmaceutical forms, such as tablets, hydrogels, micro/nanoparticles, and mucoadhesive films. Sterculia gums-based delivery systems have potential to be explored for new drug delivery systems. [Display omitted] • General properties of Sterculia gums • The used polysaccharides for preparing drug delivery systems were addressed. • Chemical modifications for drug delivery systems [ABSTRACT FROM AUTHOR]

Herein this manuscript the potential of moringa gum and sterculia gum polysaccharides has been explored for developing the hydrogel wound dressing for better wound care. The polysaccharide gum and polyacrylamide network structure was formed through grafting and crosslinking polymerization. The cryo-SEM and AFM of the films indicated the porosity in the polymer films and roughness of the polymer surface. The polymers were also characterized by FTIR, and 13C NMR studies. The release of the antibiotic drug levofloxacin from polymer dressings occurred with non-Fickian diffusion mechanism. The blood compatibility, wound fluid absorption, antioxidant activity, mucoadhesion and mechanical properties were evaluated along with O2 and H2O permeability. The drug released fitted in Korsmeyer-Peppas kinetic model. The hydrogel films were permeable to O2 and H2O vapor and impermeable to microbes in open environment and showed high wound fluid absorption, mucoadhesion and antioxidant activity.

Recently, various innovative advancements have been made in carbohydrate research to design versatile materials for biomedical applications. The current research focuses on the development of copolymeric hydrogel wound dressings (HWD) using a combination of aloe vera (AV) - sterculia gum (SG) - poly (vinylsulfonic acid) (VSA)-based with the aim to enhancing their efficacy in drug delivery (DD) applications. These hydrogel dressings were encapsulated with levofloxacin and lidocaine to address both microbial infection and pain. Copolymers were characterized by FESEM, SEM, EDS, AFM, 13C NMR, FTIR, XRD, and TGA-DTG analysis. Hydrogel exhibited a fluid absorption capacity of 4.52 ± 0.12 g per gram of polymeric dressing in simulated wound conditions. The hydrogels displayed a sustained release of drugs, demonstrating a non-Fickian diffusion mechanism. Polymer dressings revealed antibacterial, mucoadhesive, antioxidant, biocompatible and non-cytotoxic properties. Additionally, HWD displayed permeability to O 2 and water vapour, yet was impermeable to microbial penetration. Overall, the findings of physiological, biochemical and drug delivery properties demonstrated the suitability of materials for wound dressing applications. [ABSTRACT FROM AUTHOR]

Background: In recent era, pH sensitive polymeric carriers that combines the materials engineering and medicine is gaining researcher's attention as they maximizes drug concentration at site of absorption and reduces side effects for e.g. orally administered cetirizine HCl (CTZ HCl) upsets the stomach and furthermore shows high intestinal absorption. Thus, development of pH sensitive hydrogels with sufficient mechanical strength will be good candidate to address this issue. Methods: Here, we developed pH sensitive itaconic acid-g-poly(acrylamide)/sterculia gum (IA-g-poly(AM)/sterculia gum) semi-interpenetrating network (semi-IPN) by free radical polymerization technique for intestinal delivery of CTZ HCL. Results: Optimized formulation (I5) with 6% w/w IA showed negligible swelling at pH 1.2, and maximum swelling at pH 7.4. Solid state characterization of optimized formulation showed successful development of semi-IPN structure and incorporation of drug without any noticeable drug-carrier interaction. In vitro release study showed biphasic pH dependent release of CTZ HCl, where initial burst release was observed at acidic pH followed by sustained release at basic pH. Acute oral toxicity and histopathological studies confirmed the non-toxic nature of IA-g-poly(AM)/sterculia gum. Conclusion: Conclusively, developed biocompatible semi-IPN hydrogels with sufficient pH sensitivity and mechanical strength could serve as a potential carrier for intestinal delivery of CTZ HCL to maximize its absorption and reduce side effects. [ABSTRACT FROM AUTHOR]

Aims Keeping in view the therapeutic and pharmaceutical applications of sterculia gum polysaccharide in consideration, its modification has been carried out through grafting and crosslinking to develop the hydrogels for enhanced biomedical applications. Radiation method was used for formation of sterile network of sterculia gum, carbopol and graphene oxide (GO). These polymers were characterized by Cryo-SEMs, AFM, 13 C NMR solid state, swelling studies. Some biomedical properties of hydrogels like thrombogenicity, haemolytic potential, antioxidant activity, mucoadhesion and gel strength were determined along with the drug delivery studies. Scope In the present work, sterile polysaccharide gum based drug delivery system was developed for the slow delivery of gemcitabine, an anti-cancer drug, to overcome its side. Conclusions The release profile of anti-cancer drug “gemcitabine” followed non-Fickian diffusion mechanism and release profile was best fitted in Korsmeyer-Peppas kinetic model of drug release. The hydrogels were found to be non-thrombogenic, non-haemolytic, mucoadhesive and antioxidant in nature. Incorporation of the GO nano-sheets in the composite hydrogel matrix has improved its mechanical and drug delivery properties and also exerted strong influence on the network density and mesh size of the hydrogels. [ABSTRACT FROM AUTHOR]

Matrix tablets of Prednisolone were prepared by wet granulation method using various proportions of Sterculia gum with Carbopol 934P and Sterculia gum with Ethyl cellulose at 1:1, 1: .5 and 1:2 ratio. Coating was carried out by using 1:1 ratio of Eudragit L100 and Eudragit S100. All the preparation were evaluated for Pre compressional properties, Post compressional properties and in-vitro Dissolution study in different pH buffer of 0.1N HCL ,pH 7.4 , pH 6.8 in order to mimic GIT condition. Formulation shows good results with good percentage yield.

Abstract Following a request from the European Commission, the EFSA Panel on Food Additives and Nutrient sources added to Food (ANS) was asked to deliver a scientific opinion on the re‐evaluation of karaya gum (E 416) as a food additive. Karaya gum (E 416) is an authorised food additive in the EU. Karaya gum (E 416) as specified in the Commission Regulation (EU) No 231/2012 is derived from the exudates from the stems and branches of strains of Sterculia urens Roxburgh and other species of Sterculia (family Sterculiaceae) or from Cochlospermum gossypium A.P. De Candolle or other species of Cochlospermum (family Bixaceae). An acceptable daily intake (ADI) ‘not specified’ was allocated by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (JECFA), whereas the Scientific Committee for Food (SCF) allocated an ADI of 12.5 mg/kg body weight (bw) per day. Karaya gum is practically undigested and not degraded by intestinal microflora and it is most probably not or only negligibly absorbed unchanged in humans. There is no concern with respect to the genotoxicity of karaya gum from Sterculia spp. Karaya gum (E 416) from Sterculia spp. did not induce toxic effects in animals at dose levels up to 1,250 mg/kg bw per day, the highest dose tested. Karaya gum from Sterculia spp. was well tolerated in humans at dose about 100 mg/kg bw per day for 4 weeks. The Panel concluded that there is no safety concern at the refined exposure assessment for the use of karaya gum as a food additive and that there is no need for a numerical ADI for karaya gum. The Panel further concluded that exposure to karaya gum by the use of this food additive should not exceed 7,000 mg/person per day in adults, the level at which some experienced abdominal discomfort.

Hazardous effluents from textile industries being major contributors of water pollution and impose potential adverse effects on environment. In present study, Fe 3 O 4 embedded oxidized Sterculia gum/Gelatin hybrid matrix have been fabricated and evaluated for enrichment of methyl orange (MO) and methylene blue (MB). Newly synthesized matrix was characterized through powdered XRD, FTIR, FESEM, TEM and TGA. Integrated nanoparticles improved dye enrichment and facilitated removal of matrix from the aqueous solution under the influence of magnetic field. Influence of various reaction parameters viz.: contact time, adsorbent dose, initial dye concentration, temperature & pH of the adsorption medium on dye enrichment have been evaluated. Maximum adsorption (90 % and 88 % for MO and MB respectively) has been achieved. Langmuir, Freundlich and Tempkin adsorption isotherms have been evaluated. Experimental results validate well fitted Freundlich isotherm for MO and Temkin isotherm for MB. Adsorption kinetics has been analyzed through Pseudo first order, second order kinetic and intra particle diffusion models. Adsorption of both dyes was best explained via pseudo second order kinetic model. Negative value of Gibb's free energy change (−26.487 KJ mol −1 and − 24.262 KJ mol −1) for MB and MO at 303 K was an indication of spontaneity of the reaction. [ABSTRACT FROM AUTHOR]

Following a request from the European Commission, the EFSA Panel on Food Additives and Nutrient sources added to Food (ANS) was asked to deliver a scientific opinion on the re-evaluation of karaya gum (E 416) as a food additive. Karaya gum (E 416) is an authorised food additive in the EU. Karaya gum (E 416) as specified in the Commission Regulation (EU) No 231/2012 is derived from the exudates from the stems and branches of strains of Sterculia urens Roxburgh and other species of Sterculia (family Sterculiaceae) or from Cochlospermum gossypium A.P. De Candolle or other species of Cochlospermum (family Bixaceae). An acceptable daily intake (ADI) 'not specified' was allocated by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (JECFA), whereas the Scientific Committee for Food (SCF) allocated an ADI of 12.5 mg/kg body weight (bw) per day. Karaya gum is practically undigested and not degraded by intestinal microflora and it is most probably not or only negligibly absorbed unchanged in humans. There is no concern with respect to the genotoxicity of karaya gum from Sterculia spp. Karaya gum (E 416) from Sterculia spp. did not induce toxic effects in animals at dose levels up to 1,250 mg/kg bw per day, the highest dose tested. Karaya gum from Sterculia spp. was well tolerated in humans at dose about 100 mg/kg bw per day for 4 weeks. The Panel concluded that there is no safety concern at the refined exposure assessment for the use of karaya gum as a food additive and that there is no need for a numerical ADI for karaya gum. The Panel further concluded that exposure to karaya gum by the use of this food additive should not exceed 7,000 mg/person per day in adults, the level at which some experienced abdominal discomfort. [ABSTRACT FROM AUTHOR]

Recently, graphene oxide (GO) has been well explored for biomedical applications due to its stability, biocompatibility and large surface area. Herein this research, GO incorporated sterculia gum-poly(VSA) hydrogels were designed by encapsulating vancomycin antibiotic drug for use in colon specific drug delivery. The copolymers were characterized by SEMs, AFM, FTIR, XRD, solid state 13C NMR swelling studies. Some biomedical properties of the polymers were also evaluated. The pH responsive GO-sterculia-poly(VSA) hydrogels showed 3.2 ± 0.41 % haemolytic potential, 0.119 ± 0.057 N detachment force of polymer from mucosal membrane during mucoadhesion and 52.49 ± 2.38 % antioxidant activity (DPPH assay). The results indicated that GO containing hydrogels formed after crosslinking of poly(vinyl sulfonic acid) onto sterculia gum can be used for controlled drug delivery applications. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel dual crosslinked low-methoxyl (LM) pectinate–sterculia gum (SG) interpenetrating polymer network (IPN) beads was developed for intragastric ziprasidone delivery. The IPN beads were accomplished by simultaneous ionotropic gelation with zinc acetate and covalent crosslinking with glutaraldehyde. The effects of pectin and SG contents on drug entrapment efficiency (DEE, %), and cumulative drug release after 8 h ( Q 8 , %) were studied to optimize the IPN beads using a 3 2 factorial design. The optimized beads encapsulating ziprasidone HCl (F-O) displayed DEE of 87.98 ± 1.15% and Q 8 of 58.81 ± 1.50% with excellent buoyancy (floating lag time <2 min, % buoyancy at 8 h >63%) and good mucoadhesivity with the goat gastric mucosa. In most cases, the drug release behaviour obeyed Higuchi kinetics with anomalous transport mechanism. The Zn–pectinate–SG IPN beads were also characterized by SEM, FTIR, DSC and P-XRD analyses. [ABSTRACT FROM AUTHOR]

Novel floating-mucoadhesive oil-entrapped alginate beads coated with crossslinked alginate–sterculia gum gel membrane was developed for gastroretentive risperidone delivery. Oil-entrapped alginate beads containing risperidone as core were prepared by ionotropic gelation technique. Effects of polymer to drug ratio and oil to water ratio on drug entrapment efficiency (%) and cumulative drug release after 8 h (%) were studied to optimize the core beads by a 3 2 factorial design. The optimized beads (F O) demonstrated drug entrapment efficiency of 83.73 ± 0.81% and cumulative drug release of 70.84 ± 0.27% after 8 h. The biopolymeric-coated optimized beads exhibited excellent buoyancy, better ex vivo mucoadhesion and slower drug release rate. The drug release profiles of risperidone-loaded uncoated and coated beads were best fitted in Korsmeyer–Peppas model with Fickian diffusion mechanism. The beads were also examined for the drug-excipients compatibility, drug crystallinity and surface morphology by FTIR, P-XRD and SEM analyses, respectively. [ABSTRACT FROM AUTHOR]

The present study was aimed at designing a microflora triggered colon targeted drug delivery system (MCDDS) based on swellable polysaccharide, Sterculia gum in combination with biodegradable polymers with a view to specifically deliver azathioprine in the colonic region for the treatment of IBD with reduced systemic toxicity. The microflora degradation properties of Sterculia gum was investigated in rat caecal phosphate buffer medium. The polysaccharide tablet cores were coated to different film thicknesses with blends of Eudragit RLPO and chitosan and overcoated with Eudragit L00 to provide acid and intestinal resistance. Swelling and drug release studies were carried out in simulated gastric fluid, SGF (pH 1.2), simulated intestinal fluid, SIF (pH 6.8) and simulated colonic fluid, SCF (pH 7.4 under anaerobic environment), respectively. Drug release study in SCF revealed that swelling force of the Sterculia gum could concurrently drive the drug out of the polysaccharide core due to the rupture of the chitosan/Eudargit coating in microflora activated environment. The degradation of chitosan was the rate-limiting factor for drug release in the colon. Drug release from the MCDDS was directly proportional to the concentration of the pore former (chitosan), but inversely related to the Eudragit RLPO coating thickness. [ABSTRACT FROM AUTHOR]

Abstract: The current investigation deals with the development and optimization of oil-entrapped sterculia gum–alginate buoyant beads containing aceclofenac by ionotropic emulsion–gelation technique using 32 factorial design. The effect of polymer to drug ratio and sodium alginate to sterculia gum ratio on the drug entrapment efficiency (%), and cumulative drug release after 7h (%) was optimized. The optimized oil-entrapped sterculia gum–alginate buoyant beads containing aceclofenac (F-O) showed drug entrapment efficiency of 90.92±2.34%, cumulative drug release of 41.65±3.97% after 7h in simulated gastric fluid (pH 1.2), and well buoyancy over 8h in simulated gastric fluid (pH 1.2) with 5.20min buoyant lag-time. The in vitro drug release from these buoyant beads followed Korsmeyer–Peppas model (R 2 =0.9866–0.9995) with anomalous (non-Fickian) diffusion drug release mechanism. These new sterculia gum–alginate buoyant beads containing aceclofenac were also characterized using SEM, FTIR, and P-XRD analysis. [Copyright &y& Elsevier]

Abstract: In view of the pharmacological importance of sterculia gum and drug delivery devices based on hydrogels, the present study is an attempt to synthesize sterculia gum and poly(AAm) based hydrogels by using N,N′-MBAAm as crosslinker and ammonium persulfate as initiator. The polymeric networks were characterized by SEMs, FTIR and swelling studies. The release dynamics of model anti-ulcer drug (ranitidine hydrochloride) from the hydrogels has been studied for the evaluation of the release mechanism and diffusion coefficients. The values of the diffusion exponent ‘n’ (0.43, 0.44 and 0.62) and gel characteristic constant ‘k’ (8.669×10−2, 8.016×10−2 and 2.964×10−2) have been obtained, respectively, in distilled water, pH 2.2 buffer and pH 7.4 buffer. The release of drug from the hydrogels occurred through Fickian diffusion mechanism in distilled water and in pH 2.2 buffer, and through non-Fickian diffusion mechanism in pH 7.4 buffers. [Copyright &y& Elsevier]

Abstract: The present study deals with the modification of sterculia gum to develop the novel wounds dressing for the delivery of antimicrobial agent (tetracycline hydrochloride). The sterculia crosslinked PVA (sterculia-cl-PVA) hydrogels were characterized by FTIR and swelling studies. For the evaluation of swelling and drug release mechanism, the swelling kinetics and in vitro release dynamics of model drug from this matrix were studied in solution of different pH and simulated wounds fluid. Per gram of polymer has taken (8.3±0.1) g of simulated wounds fluid and has released (0.820±0.6) mg of drug in the simulated fluid. The value of the ‘n’ (0.84) indicates the non-Fickian diffusion mechanism for the release of drug in simulated fluids. [Copyright &y& Elsevier]

Abstract: The present paper deals with the modification of the sterculia gum with methacrylic acid (MAAc) to hydrogels for use in drug delivery. The hydrogels were characterized by SEMs, FTIR and swelling studies. The release dynamics of model anti-ulcer drug (ranitidine hydrochloride) from the hydrogels has been studied for the evaluation of the release mechanism. The values of the diffusion exponent ‘n’ (0.55, 0.54 and 0.59) and gel characteristic constant ‘k’ (2.109×10−2, 3.698×10−2 and 2.427×10−2) have been obtained, respectively, in distilled water, pH 2.2 buffer and pH 7.4 buffer. The release of the drug from the hydrogels occurred through non-Fickian diffusion mechanism. [Copyright &y& Elsevier]

Abstract: In order to modify the sterculia gum polysaccharide, to develop the hydrogels meant for the drug delivery, we have prepared sterculia gum, 2-hydroxyethylmethacrylate (HEMA) and acrylic acid (AAc) based hydrogels by radiation-induced crosslinking polymerization. Polymeric networks (hydrogels) thus formed were characterized with SEMs, FTIR,TGA and swelling studies which were carried out as a function monomers concentration, radiation dose, amount of sterculia contents in the polymer matrix and nature of the swelling medium. This paper discusses the swelling kinetics of the hydrogels and release dynamics of anti-diarrhea model drug ornidazole from the hydrogels to evaluation of swelling and drug release mechanism. Diffusion exponent ‘n’ have 0.73, 0.56 and 0.61 values and gel characteristic constant ‘k’ have 1.28×10−2, 2.95×10−2 and 2.14×10−2 values in distilled water, pH 2.2 buffer and pH 7.4 buffer. The release of drug from the polymer matrix occurred through non-Fickian diffusion mechanism. The values for the late time diffusion coefficients have been lower than the values of initial and average diffusion coefficients. It reflects that in the initial stages rate of release of drug from polymer matrix was higher as compared to the late stages, it means after certain time the drug release occurred in controlled manner. [Copyright &y& Elsevier]

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[Display omitted] • Gamma radiation designed hydrogels were porous, pure and sterile. • Polymer showed higher drug release in ACSF. • The drug release occurred via Fickian diffusion mechanism. • The drug release profile was best fitted in First order kinetic Model. • The polymeric hydrogels were non thrombogenic, non haemolytic and antioxidant nature. As the brain injury causes persistent neurological disorders that lead to the loss of neuron functions. The blood–brain-barrier limits the bioavailability of drugs required in therapeutic level. Hydrogel dressing can provide the localized drug release to the injured brain tissues that can reduce the limitations of the other drug delivery formulations. In the present article, sterculia gum and alginate polysaccharides were explored to form hydrogel dressing by radiation method for use in brain drug delivery. These dressings were characterized by AFM, XRD, FTIR, and 13C NMR. The content of the artificial cerebrospinal fluids absorbed by sterculia-alginate dressing was 19.60 ± 0.35 g. The release of citicoline drug, a nerve regenerative agent, occurred in controlled manner through Fickian mechanism and followed first order kinetic model. The porous dressings were permeable to O 2 and H 2 O and were biocompatible and antioxidant. Since the hydrogel dressings were prepared by radiation method so the resultant material was pure and sterile and could be explored for its application in brain drug delivery during brain injury. [ABSTRACT FROM AUTHOR]