EFFECTS OF PAMAM DENDRIMERS ON THE SOLUBILITY OF KETOPROFEN

Abstract

The aim of this study was to study the effect of polyamidoamine ( PAMAM) dendrimers on the aqueous solubility of ketoprofen and investigate the mechanism of solubilization.PAMAM dendrimers of G1.0,G1.5,G2.0,G2.5,G3.0 and G3.5 were used as drug carriers of ketoprofen.The effects of pH and concentration of the dendrimers on the solubility of ketoprofen were studied by UV spectroscopy.In addition,the computational simulation was used to investigate the mechanism of interaction between PAMAM dendrimers and ketoprofen.Results showed that the pH,generation size,and concentration influenced the solubilization of ketoprofen.The solubility of ketoprofen increased with the increase of pH ,generation size,and concentration of PAMAM dendrimers at pH 4.0 ～ 6.0.Both amino and ester terminated dendrimers caused the increase in ketoprofen solubility.However,at each pH,the solubility of ketoprofen was greater in the presence of amino- terminated dendrimers compared to the ester-terminated dendrimers possessing the same number of surface functional groups.The results of computational simulation show that interaction between ketoprofen and PAMAM dendrimers is mainly electrostatic force.Its mechanism of solubilization maybe an electrostatic interaction between the carboxyl group of ketoprofen and the primary amines or tertiary amines of PAMAM dendrimers.