Roop Narayan Gupta

Evaluation of gum of Moringa oleifera as a binder and release retardant in tablet formulation

The present study was undertaken to find out the potential of gum from Moringa oleifera to act as a binder and release retardant in tablet formulations. The effect of calcium sulphate dihydrate (water insoluble) and lactose (water soluble) diluent on the release of propranolol hydrochloride was studied. The DSC thermograms of drug, gum and mixture of gum/drug indicated no chemical interaction. Tablets (F1, F2, F3, and F4) were prepared containing calcium sulphate dihydrate as diluent, propranolol hydrochloride as model drug using 10%, 8%, 6% and 4% w/v of gum solution as binder. Magnesium stearate was used as lubricant. Physical and technological properties of granules and tablets like flow rate, Carr index, Hausner ratio, angle of repose, hardness, friability and disintegration time were determined and found to be satisfactory. Tablets were prepared by wet granulation method containing calcium sulphate dihydrate as excipient, propranolol hydrochloride as model drug using 10%, 20% and 30% of gum as release retardant, magnesium stearate was used as lubricant. Similarly tablets were prepared replacing lactose with calcium sulphate dihydrate. Despite of the widely varying physico-chemical characteristics of the excipients, the drug release profiles were found to be similar. The drug release increased with increasing proportions of the excipient and decreased proportion of the gum irrespective of the solubility characteristics of the excipient. The values of release exponent ‘n’ are between 0.37 and 0.54. This implies that the release mechanism is Fickian. There is no evidence that the dissolution or erosion of the excipient has got any effect on the release of the drug. The t50% values for tablets containing calcium sulphate dihydrate were on an average 10%-15% longer than the tablets containing lactose as excipient. These relatively small differences in t50% values suggest that the nature of excipient used appeared to play a minor role in regulating the release, while the gum content was a major factor.

Preparation and evaluation of gels from gum of Moringa oleifera

The present study was undertaken with an objective to find out the gelling potentials of a natural gum obtained from plant Moringa oleifera . The gum was extracted by using water as solvent and precipitated using acetone as non-solvent. Physical characteristics such as, solubility, swelling index, loss on drying, and pH were studied. Diclofenac sodium was used as model drug for the formulation of gels. Seven batches of drug loaded gels with concentration of mucilage ranging from 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, and 8.5 were formulated by using glycerin as plasticizer and methyl paraben as preservative. The pH, viscosity, and in vitro diffusion profiles were studied. The gels prepared with 8.0% of mucilage were found to be ideal and comparable with a commercial preparation.

Development, in vitro and in vivo characterization of Eudragit RL 100 nanoparticles for improved ocular bioavailability of acetazolamide

Abstract Glaucoma is characterized by increased intra ocular pressure (IOP) which results in blindness if left untreated. Acetazolamide (ACZ) is used to treat glaucoma since long back. Since it is a Class IV drug [According to Biopharmaceutics Classification System (BCS)], so its topical delivery results in poor ocular bioavailability. Objective of the present study is to increase the topical ocular bioavailability and to sustain the release of drug for longer time. ACZ-loaded Eudragit® RL 100 nanoparticle suspension (ACZ-E-NPs) was prepared by the nanoprecipitation method. Ratio of organic to aqueous phase and composition of organic phase were altered to get the best formulation. Formulations prepared with acetone and methanol as organic phase were smallest in size. EE was in the range of 57.8% to 68.5%. According to drug release study almost all the formulations released 80% of drug in 8 h duration. The kinetics of drug release showed that the drug release pattern followed Higuchi’s model (highest R2 values) and further it was fitted to the Korsemeyer–Peppas model, which showed the release was as per Fickian diffusion. IOP lowering effects of plain drug solution and ACZ-E-NPs were compared in adult male albino rabbits with a Riester Tonometer. The data revealed that the ACZ-E-NPs lower the IOP for longer time and of higher magnitude also. The difference was significant (p < 0.001). Short-term stability study showed that none of the formulations was having remarked difference in their physicochemical properties after 6 months of storage at various temperatures.

Immune-stimulating potential of cell envelope proteins from Vibrio cholerae associated to chitosan microparticles: an in vitro study.

Abstract Context: Cholera is a severe diarrheal disease that remains an important cause of illness and death in many parts of the world. Objective: This study has been designed to check the immune-stimulating potential of antigens in their native and associated form as chitosan microparticles in vitro. Material and methods: Chitosan microparticles were prepared by the ionic gelation technique. The cell envelope proteins (CEPs) isolated from Vibrio cholerae were loaded as antigenic material. The prepared microparticles were characterized for their morphology, loading efficiency, particle size, and zeta potential. Results: The average particle size of CEPs-loaded chitosan microparticles was 2.24 µm and the zeta potential of loaded microparticles was less than blank microparticles. The in vitro release studies of CEPs from CEPs-loaded chitosan microparticles exhibited slow and extended release over a period of time. The higher release of cytokine profile, including interferon γ (IFN-γ), tumor necrosis factor α (TNF-α), and interlukin-6 (IL-6), was observed for CEPs-loaded chitosan microparticles in comparison to CEPs as native antigen. Discussion: The particle size of microparticles was within the range for phagocytosis by macropahges, which affects the immunogenicity. The decrease in zeta potential from blank to loaded microparticles further confirms the loading of antigen. The slow and extended release of CEPs provides continuous stimulus of antigen for a longer period of time. The cytokine profiling has shown the advantage of loaded microparticles over native antigen. Conclusion: The in vitro release studies and cytokine profiling strongly suggested that CEPs-associated chitosan microparticles could be a potential candidate for oral vaccination against Vibrio cholerae.