D.V.R.N Bhikshapathi

Nateglinide is an anti-diabetic drug that lowers the blood glucose levels by stimulating insulin secretion from pancreas. Because of low solubility and bioavailability, its usage is limited. In the present study solid dispersions of Nateglinide were prepared by solvent evaporation method and evaluated through various steps for biological correlation. Nateglinide solid dispersions were prepared using PEG 6000, Pluronic F 127 and Labrafil M 1944. A 3-factor, 3-level Central composite design employed to study the effect of each independent variable on dependent variables. X-ray diffraction was used to analyze the crystallinity and FTIR was used to analyze the drug and excipient compatibility. Scanning electron microscopy was performed to analyze the surface of solid dispersion samples. The correlation coefficient showed that the release profile followed Higuchi model (R2= 0.95836). From Korsmeyer peppas model, the release exponent, n was found to be 0.80635 (0.43 < n < 0.85) and followed anomalous behaviour and hence release mechanism was indicative of diffusion. From in vitro dissolution studies it was proved that a Nateglinide solid dispersion may achieve good formulation capability for pharmaceutical manufacturer by increasing solubility and dissolution rate. Key words: Nateglinide, Diabetes mellitus, solid dispersions, solubility, Central composite  

The aim of the present research is anti diabetic activity of polyherbal formulation comparing with individual plant extractions. The anti diabetic activity of a polyherbal formulation was evaluated in using Alloxan ?- cytotoxin induced chemical diabetes in a wide variety of wister rats. Methanolic extract of the poly herbal formulation, prepared from powder of plants Fruits of Momordica charantia, stem and root of Tinospora cordifolia , aerial parts of Andrographis peniculeta and wood of Pterocarpus marsupium and leaves of Gymnema sylvestre  was subjected to phytochemical test and pharmacological screening of Anti diabetic activity at a dose level 400mg/kg. The PHME (400mg/kg) treated diabetic rats show mean (±SEM) fasting serum glucose of 253.11±3.41mg/dl on day 0 which was reduced to 161.43±3.55mg/dl on day 7, 107.45±4.52mg/dl on day 14  . These changes in fasting serum glucose illustrate that the diabetic rats treated with PHME (400mg/kg) show a progressive and significant (p?0.05) reduction in fasting serum glucose during the treatment period in comparison to diabetic group of rats. It was concluded that individual extraction shows the activities but in combination of plants it shows synergistic effect so poly herbal extraction is useful more when compared with given in individual plants.

In the present research work mucoadhesive microspheres of Cimetidine were prepared using Ionotropic gelation technique. All the microspheres were characterized for particle size, scanning electron microscopy, FT-IR study, DSC, percentage yield, drug entrapment, stability studies and for in vitro release kinetics and found to be within the limits. Among all the formulations M12 was selected as optimized formulation based on the physicochemical and release studies. In vitro drug release study of optimized formulation M12 showed 99.12% after 12 h in a controlled manner, which is essential for anti ulcer therapy. The innovator Cimetine conventional tablet showed the drug release of 96.15% within 1 h. The drug release of Cimetidine optimized formulation M12 followed zero order and Higuchi kinetics indicating diffusion controlled drug release.

The purpose of the research was to prepare and evaluate Roxatidine acetate HCl floating microspheres by ionotropic gelation method. Fourteen formulations were prepared, among all the formulations F13 was selected as optimized formulation based on the micromeretic and evaluation parameters including drug release studies. In the in vitro release study of formulation, F13 showed 95.65% drug release after 12 h in a controlled manner, which is desired for disease like peptic ulcer. In vitro release profiles from optimized formulation F13 were applied on various kinetic models. The best fit with the highest correlation coefficient was observed in zero order and Higuchi model, indicating diffusion controlled principle. The innovator Rotane 150 mg conventional tablet showed the drug release of 96.45% within 1 h. FT-IR and DSC analyses confirmed the absence of drug-polymer interaction. The results obtained from evaluation and performance study of different types of Roxatidine microspheres showed that system may be useful to achieve a controlled drug release profile, reduce the dose of drug, dosing frequency and improve patient compliance when compared with marketed product. Key words: Roxatidine, buoyancy, HPMC, gum olibanum, microspheres.