Metformin microspheres with sodium alginate alone and in combination with gellan were prepared using an emulsion-cross linking method. The prepared microspheres were evaluated for their physico-chemical characteristics like particle size, morphology using SEM, incorporation efficiency, equilibrium water content (swelling) and in vitro drug release. The effect of various formulation variables like polymer concentration (sodium alginate; and proportion of gellan in microspheres prepared by a combination of sodium alginate and gellan), drug loading, crosslinking agent concentration and cross-linking time on the in vitro dissolution of the prepared microspheres were evaluated. The results showed that both the particle size and the incorporation efficiency were proportional to the polymer concentration. In case of microspheres containing both sodium alginate and gellan, the mean diameter and the incorporation efficiency were higher than the corresponding microspheres containing only alginate, both increasing with an increase in proportion of gellan. The prepared microspheres were found to be discrete and spherical in shape and were successful in sustaining the drug release for 8 hours. Incorporation of gellan caused a significant decrease in drug release. The release followed a biphasic profile, in all cases, characterized by an initial phase of moderate drug release followed by a phase of higher release. Further, the kinetic treatment of the dissolution data revealed the prevalence of matrix diffusion kinetics.

The overall prevalence of dyslipidemia in India in 2013 was 10 % to 73 %. The prevalence of hyperlipidemia is more in females (33.2 %) than in males (32.4). On an average 32.8 % population is suffering from hyperlipidemia. The objective of the present study is to prepare and evaluate the stomach specific floating microspheres of simvastatin. Simvastatin microspheres were prepared by ionotropic gelation method using polymers such as sodium alginate, guar gum, pectin and carbopol. Total 12 formulations were prepared by using the above polymers. The prepared microspheres were evaluated for their appearance, solubility, physical properties (bulk density, tapped density, compressibility index, angle of repose), particle size, swelling index, SEM studies, buoyancy property, entrapment efficiency, in-vitro dug release and drug release kinetics. All formulations showed compliance with pharmacopoeial standards. The in-vitro drug release studies were conducted using USP dissolution apparatus type II (paddle) in 900 ml of 0.1 N HCl for first 2 h, next 1 h in 6.8 pH phosphate buffer and the remaining 9 h in 7.4 pH phosphate buffer. Surface morphology (SEM analysis) was conducted with F2, F7, F10 and F12 formulations. Drug polymer interaction studies (FTIR) were performed with all the polymers. The microspheres were smooth and elegant in appearance, showed no visible cracks as confirmed by SEM and FTIR studies indicated the lack of drug polymer interaction. Based on dissolution data, formulation F12 was the best formulation with a drug release of 98.96 %. The in-vitro release data of all microsphere formulations were plotted in various kinetic equations to understand the mechanisms and kinetics of drug release. The drug release kinetics of formulation F12 was of zero order with non-fickian mechanism according to Korsmeyer-Peppas equation.

The objective of this research work was to develop extended release tablets (Twice in a day) of Tramadol Hydrochloride using different Hydrophilic polymers like HPMC K15M, HPMC K4M, Metalose 60SH50, Carbopol 971P, Sodium alginate, Xanthan gum by direct compression method. Various amounts of polymers was used in the twenty four proposed formulations (F1 to F24) for the study of release rate retardant effect at 10 %, 15 %, 20 %, 25 % of total weight of tablet matrix respectively. Then the tablets were evaluated in terms of their physical parameters (weight variation, hardness, friability and thickness), drug content and in-vitro release studies. All the formulations showed compliance with pharmacopoeial standards. The i n -vi t ro dissolution study were conducted using USP dissolution apparatus type-II (paddle method) in 900 ml 0.1 N HCl for first 2 h and remaining 10 h performed in 6.8 pH phosphate buffer at 100 rpm for a total period of 12 h. Based on the dissolution data comparison with innovator product, formulation F14 was found as the best formulation. The drug release of formulation F14 followed First Order kinetic model and the mechanism was found to be non-Fickian/anomalous according to Korsmeyer-Peppas equation.