The microparticles were then observed with the scanning electron microscope (Leica Electron Optics, Cambridge, USA) at 10 kv).13 Release of Glibenclamide from the microparticles, was studied in phosphate buffer of pH 7.4 (900 ml) using Eight Station Dissolution Rate Test Apparatus (M/s. Electrolab) with a paddle stirrer at 100 rpm and at 37 °C ± 0.5 °C. A sample of microparticles equivalent to 5 mg of Glibenclamide was used in each test. Samples were withdrawn through a filter (0.45) at different time intervals and were assayed at 228 nm for Glibenclamide using Shimadzu double beam UV spectrophotometer. The drug release experiments

were conducted in triplicate.14 The rate and release mechanism of Glibenclamide from the prepared microparticles were analyzed by fitting the dissolution data into,15 zero-order equation, Q = Q0 − k0t(1),where Q is the amount of drug released at time selleck products t, and k0 is the release rate. First order equation, Ln Q = Ln Q0 − k1t (2), where k1 is the release rate constant and Higuchi’s equation, Q = k2t1/2 (3) where Q is MI-773 the amount of the drug released at time t and k2 is the diffusion rate constant. The dissolution data was further analyzed to define the mechanism of release by applying the dissolution data following the empirical equation, Mt/Mα = Ktn (4), where Mt/Mα is the fraction of drug released at time t. K is a constant and n characterizes the mechanism of drug release from

the formulations during crotamiton dissolution process. The formulation was subjected to accelerated stability studies as per ICH (The International Conference of Harmonization) guidelines. The optimized formulation was sealed in an aluminum foil and stored at 25 ± 2 °C, 60 ± 5% RH and at 40 ± 2 °C, 75 ± 5% RH for 3 months.16 Microparticles were periodically removed and evaluated for physical characteristics

and in-vitro drug release. Glibenclamide microparticles were successfully formulated by emulsion solvent evaporation method. The microparticles were formulated by using Cellulose Acetate as rate retardant polymer. In this formulations span 80 and tween 80 used as surfactant and the optimum concentration used is 1% w/v. A total of eight batches were formulated by varying the process variables like change in polymer concentration and by varying surfactants. The detailed composition of microparticles was shown in Table 1. These microparticles were characterized for drug–excipient compatibility studies, percentage yield, flow properties, size analysis, % Drug Content, % Encapsulation Efficiency, In vitro release studies and stability studies. Glibenclamide (Fig. 1) shows prominent peaks at wave numbers were 3311.19, (N–H), 2929.06 (C–H), 2851.28 (O–H), 1449.29 and 1517.12 (N=O), 1154.22 (C–N) and 1010.89 (C–O). The spectra of optimized microparticles (Fig. 2) exhibited all the principle peaks present in the Glibenclamide pure drug which indicates the stable nature of the drug during encapsulation.