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Purpose To investigate the plausibility of delivering brain derived neurotrophic factor (BDNF) to the brain via nose to brain pathway using chitosan as barrier modulating agent. Methods The effect of different viscosity grades chitosan (low viscosity, medium viscosity and high viscosity) at different concentrations on the permeation of fluorescein isothio-cyanate dextran (FD 40K) across bovine olfactory mucosa was studied using Franz diffusion cells. The best viscosity grade chitosan was used to carry out the permeation studies of BDNF. Pharmacokinetic and pharmacodynamic studies were carried out in Sprague dawley rats upon intranasal/i.v administration of different formulations. Results The medium viscosity grade chitosan was more efficient in enhancing the permeation of FD 40K across the olfactory mucosa compared to other two grades of chitosan. In case of BDNF, medium viscosity grade chitosan (0.25 % w/v) was found to enhance the permeation by ~14 fold over control (18.78 ± 16.69 ng/cm2). The brain bioavailability of group of rats administered intranasally with BDNF solution containing chitosan was significantly enhanced by ~13 fold compared to group of rats administered with same concentration of BDNF solution without chitosan. Moreover, in case of rats subjected to immobilization stress the BDNF solution containing chitosan significantly decreased the immobility time. Conclusions Intranasal formulations containing chitosan as barrier modulating agent significantly enhanced the brain bioavailability of BDNF. The delivery of BDNF was found to counteract the stress induced depression in rats.

Objective: The objective of this research work to design nasal microspheres of ropinirole hydrochloride (HCL) using different mucoadhesive polymers by adopting the suitable technique. To study the influence of formulation and process variables on microsphere formation and release characteristics. To perform the physicochemical characterization of the prepared microspheres. To carry out in vitro drug release studies and to explore the release behavior using various kinetic models.Methods: Experiments were performed with ropinirole HCL as a drug, chitosan, guar gum, carbopol 974P as a polymer. Span 80 and Tween 80 used light liquid paraffin, concentrated hydrochloric acid as solvent.Result: The in vitro drug release studies were conducted for all the formulations, that is, F1-F21 in 250 ml phosphate buffer pH 6.6 for 12 hrs. Among them, F15 showed 82.7±0.23% drug release and F21 showed 81.2% in 12 hrs in a sustained manner.Conclusion: Microspheres were formulated by emulsion solvent evaporation technique using different polymers. Apart from preventing nasal irritation, the microsphere possesses two major advantages over plain solutions, one is a high solubilization capacity for ropinirole HCL that exceeds their aqueous solubility and thus allows a reduction in the application volume. The results of this work indicate that intranasal microsphere of ropinirole may be beneficial for the treatment of Parkinson’s disease.

Problem statement: UlGen, a Polyherbal formulation, was investigated for its possible Ulcero-protective activity in ulcerogen and Cold-restraint stress induced Wister rats (Rattus rattus). Oral administration of UlGen, at a dose of 800 mg kg −1 significantly protected the onset of coldresistance stress induced ulcerations. Approach: It significantly inhibited gastric ulceration induced by alcohol and aspirin. Control group: Alcohol 80% induced ulcer was 42.00±2.30 and in UlGen treated rats showed 10.00±1.62. Using alcian blue stain to study the mucus secretion by mucosal cells carried out histological examination of gastric glandular mucosa. Results: The volume and acidity of gastric juice in pyloric-ligated rats was reduced in treated rats. Gastric volume (mL 100 g −1 ) in control rats showed 4.12±0.32 and in UlGen treated rats showed 2.50±0.20. Conclusion: UlGen, Cytoprotective effect may be due to the enhancement of defensive mechanism through an improvement of gastric cytoprotection as well as acid inhibition.

: Photocatalytic oxidation is a promising tool for waste water treatment and decomposition of biologically non digestible substances. Immersed nanoscale catalyst particles from semiconductor materials such as TiO2 and ZnO can be excited by absorbed UV radiation, leading to hydroxyl-ion formation at the surface of the semiconductor and oxidative degradation of pollutants. This contribution deals with reactors equipped with catalyst coated light guides to combine the advantages of immobilized catalysts with nearly homogeneous irradiation. With experimental and theoretical methods the coupling and decoupling of radiation were investigated and the performance of catalyst coated light guides was tested by means of methylene-blue degradation. Radiation models, known from the recent literature, use single ray, parallel ray or multi ray models to approximate the light transmission. These models neglect Fresnel reflection and consider only coupling into the light guide. In this study, the LED was simulated as a Lambertian radiator using 104 rays with angle dependent intensities. This well-known model was extended with Fresnel-reflection, which predicted the measured coupling efficiencies accurately. The simulations predict the decoupling and catalyst activation at the lateral surface of the light guide for two boundary cases, ideal matt and ideal reflective surfaces. To generate matt surfaces, the light guides were either scratched or coated with TiO2 p25 nanopowder. Sol-gel coating methods were used, to create reflective surfaces. When using matt surfaces, the decoupling rate is very high: 80% of the radiant flux exits the light guide in less than 10 cm. If light guides with reflective surfaces are used, the radiant flux leaving the light guide is low: less than 10% of the radiation exited the light conductor in the first 10 cm. Methylene-blue degradation, seen as a model reaction, was used to determine the reactor performance by comparing the pseudo first order reaction coefficients. Due to the uniform light distribution along the length of the light guides and the resulting even formation of reactive radicals, the quantum yield was increased by a factor of 3, using sol-gel coated light guides, rather than powder coated light guides.