Improved solubility and stability of aripiprazole in binary and ternary inclusion complexes using methyl-β-cyclodextrin and L-arginine.

The aim of this study was to improve the solubility of aripiprazole (ARP) by fabricating binary and ternary inclusion complexes with methyl-β-cyclodextrin (MβCD) and L-Arginine (LA). Physical mixing and lyophilization were used in the following molar ratios: 1:1, 1:2.5, 1:4, 1:9, 1:1:1, 1:1:0.27, 1:4:1, 1:9:1, 1:3.6:3.6. The developed formulations were analyzed by solubility and dissolution. They were characterized by FTIR, XRD, DSC, SEM and TGA. Ternary formulations prepared by the lyophilization method showed improved dissolution rates in simulated gastric fluid (SGF). The results showcased that the addition of MβCD and LA in inclusion complexes enhanced the solubility and decreased crystallinity. The amorphous nature of Aripiprazole in lyophilization was confirmed by XRD diffractograms. Drug release was dominated by the first-order kinetics (R2 = 0.9932) with the Fickian type of diffusion mechanism (n<0.450). LY18, LY19, LY20 and LY21 have the highest solubility (30, 35, 43 and 48 times higher than the pure drug respectively). Furthermore, it was observed that the method of preparation, as well as a specific drug to polymer and amino acid ratio, are critical for achieving high drug solubility and stability. These complexes appeared to be a promising product for the development of new drug delivery systems.