The objective of this present investigation was to develop and formulate floating sustained release matrix tablets of s (-) atenolol, by using different polymer combinations and filler, to optimize by using surface response methodology for different drug release variables and to evaluate the drug release pattern of the optimized product. Floating sustained release matrix tablets of various combinations were prepared with cellulose-based polymers: Hydroxypropyl methylcellulose, sodium bicarbonate as a gas generating agent, polyvinyl pyrrolidone as a binder and lactose monohydrate as filler. The 32 full factorial design was employed to investigate the effect of formulation variables on different properties of tablets applicable to floating lag time, buoyancy time, % drug release in 1 and 6 h (D1 h,D6 h) and time required to 90% drug release (t90%). Significance of result was analyzed using analysis of non variance and P < 0.05 was considered statistically significant. S (-) atenolol floating sustained release matrix tablets followed the Higuchi drug release kinetics that indicates the release of drug follows anomalous (non-Fickian) diffusion mechanism. The developed floating sustained release matrix tablet of improved efficacy can perform therapeutically better than a conventional tablet.

The objective of this investigation was to develop an oral sustained release formulation of linezolid that would maximize the duration of active drug concentration in the extracellular fluid, thus assuring the therapeutic efficacy. This rationale was based on the observation that the an efficacy of linezolid depends mainly on the length of time that bacteria are exposed to antibiotic concentrations above the minimum inhibitory concentration (T>MIC). linezolid sustained release tablets were prepared by wet granulation method. A full factorial design for two-factor three levels was employed systematically to optimize drug release profile at 1, 4, 8 and 16 h. Film-coated sustained release matrix tablet exhibited fickian diffusion drug release kinetics approaching Higuchi model. The significance of the results was analyzed using analysis of non-variance (ANOVA) and P MIC for at least 24 hours.