Research Journal of Science and Technology

M. Surendra ¹, T. Venkateswara Rao ¹

Affiliations
1 Department of Pharmaceutics, Bapatla College of Pharmacy, Bapatla, Guntur (D.t), Andhra Pradesh, IN
2 Department of pharmaceutics, Bapatla College of Pharmacy, Bapatla, Guntur (D.t), Andhra Pradesh, IN

Abstract

Solid dispersion is the science of dispersing one (or) more active ingredients in an inert carriers (or) matrix at solid state prepared by melting solvent method (or) solvent evaporation method. Sparingly water soluble drugs often show an erratic dissolution profile in gastrointestinal fluids which consequently results variable oral bio-availability. To improve the dissolution and bioavailability of these drugs, various techniques such as solvent evaporation method, melting method, super critical fluid process, spray drying, lyophilisation, melt agglomeration, extrusion kneading method. The various inert carriers such as acids, polymeric materials, insoluble (or) enteric polymers, surfactants etc. PEG, PVP, lactose, Mannitol, Cyclodextrins and HPMC were used to increased solubility. Solid dispersions were prepared by solvent evaporation method. Solid dispersions of ibuprofen were prepared to increase its aqueous solubility using carriers such as mannitol, urea, and sorbitol. Ibuprofen solid dispersions were prepared in 1:1, 1:2 and 1:3 ratios of the drug to carriers (w/w). The prepared solid dispersion were evaluated for physical parameters like Angle of repose, Bulk density, Carr’s index, Hausner ratio and Invitro drug release studies. Invitro drug release profile of solid dispersions were comparatively evaluated and also studied against pure Ibuprofen. Higher dissolution rate were exhibited by solid dispersions containing 1:3 ratio of Ibuprofen with urea, the rate of drug release was depended on the type, ratio of drug to carrier and method of dispersions.

Keywords

Solid Dispersions, Ibuprofen, Carriers, Solvent Evaporation Method.

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Y. Sirisha ¹, T. Venkateswara Rao ¹

Affiliations
1 Bapatla College of Pharmacy, Bapatla Educational Society, Bapatla, Guntur District, Andhra Pradesh-522101, IN

Abstract

Carvedilol is a non selective α and β receptor blocker which undergoes extensive hepatic first pass metabolism by liver and has poor oral bioavailability of 25% - 30%. In the present investigation Carvedilol was formulated as a bilayered buccal adhesive tablets in order to avoid the firstpass effect and decrease the drug loss using different polymers and excipients. Twelve formulations were made using different concentrations (17%w/w, 35%w/w, 53%w/w) of Carbopol934P, HPMC (3500-6000cps), HPC and Guar gum. The formulations were tested for %weight variation, hardness, Friability, %Drug content, in-vitro drug release, surface pH, Swelling index and Mucoadhesive strength. Mucoadhesive strength was determined by the modified balance method in grams and was found to be between 27.75±0.234gm to 75.94±0.146gm and Surface pH was found to be 7. In-vitro release studies revealed that as polymer concentration increases from 17% to 53%w/w, rate of drug release was retarded and the data was fitted into pharmacokinetic models. Among all other formulations, formulations (F₄,F₈ and F₁₁) containing 17%w/w HPMC, 35%w/wHPC and 35%w/w Guar gum were found to be best as the release was retarded upto 8.5 hours and they have good mucoadhesive strength and they follow zero order with non-fickian diffusion mechanism.

Keywords

Bilayered Buccal Tablets, Carvedilol, Carbopol934P, HPMC, HPC, Guar Gum.

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