Preparation and evaluation of Di-component and Tri-component molecular inclusion complexes of silymarin

The objective of the present investigation is to evaluate the effect of polyvinylpyrrolidone and beta-cyclodextrin over solubility and dissolution silymarine. The aqueous solubility of silymarine was increased in presence of β-cyclodextrin and polyvinylpyrrolidone alone as well as in combinations. Solid inclusion complexes of silymarine– β-cyclodextrin in1:1 molar ratio were prepared with and without polyvinylpyrrolidone by kneading method then evaluated for solubility, dissolution and physical nature by FTIR, XRD and 1H-NMR. Tri-component molecular inclusion complexes exhibited better solubility, dissolution rate and dissolution efficiency as compared to di-component complexes. Silymarin in vitro releases at 15 min were 29% and 55% from pure silymarin bulk and di-component complexes respectively; however tri-component complexes exhibited almost complete release. Beta-cyclodextrin alone causes a approximately 1. 3 fold increase in the dissolution of silymarin, however, beta-cyclodextrin in combination with polyvinylpyrrolidone exhibited approximately two fold increase in the dissolution of silymarin.