Dissolution enhancement of Tacrolimus by surface solid-dispersion technique

Abstract

The work was aimed to increase the dissolution rate of tacrolimus by surface solid dispersion technique. being insoluble in water, tacrolimus exhibits very low drug dissolution profiles and hence it was planned to modify the surface area and thereby to increase the absolute surface area of tacrolimus by using insoluble and hydrophilic polymers. the surface modified solid mixture of tacrolimus were formulated by surface solid dispersion technique using polymers like sodium starch glycolate (ssg), microcrystalline cellulose (mcc), cross carmellose sodium (ccs), modified starch (ms) and gum karaya (gk). The various ratios of drug:polymer (1:0.5, 1:1, 1:2, 1:3, 1:4 and 1:5) were used to develop the solid mixtures. The obtained solid dispersions were evaluated for percentage yield, drug content and in-vitro drug release. In-vitro dissolution study for all surface solid dispersions was conducted in pH 6.8 pbs environment. Drug release patterns of tacrolimus from raw sample and surface solid dispersions were compared. The results were evidenced that all surface solid dispersions have shown profound increase in dissolution when compared with that of raw sample. Among all surface solid dispersions, the drug release was found to be highest in mixture of tacrolimus with mcc at 1:5 ratio in 120 minutes. Overall, surface dispersion technique can be employed to important naturally obtaining moieties without many hassles.