Magadiite as carrier of procainamide hydrochloride and controlled release of drugs

Magadiite (Mag) may be a promising drug carrier because of its advantages. In the present work, the procainamide hydrochloride [4-amino-n-(2-diethylaminoethyl)benzamide hydrochloride, PA] was loaded into magadiite, the stability constant of the product Mag-PA was estimated to be 60.39. The loading capacity of Mag-PA for cationic PA was estimated to be 9.10%. Drug release was carried out in phosphate buffer solution (PBS, pH = 7.40, simulating intestinal fluid) and HCl solution (pH = 1.35, simulating gastric fluid), respectively. The detection limits of the PA in PBS (pH = 7.40) and HCl (pH = 1.35) are about 0 ~ 0.0638 g/L and 0 ~ 0.0812 g/L, respectively. The releasing percentages of PA are about 48.86% after 120 h in the PBS and 76.23% after 700 min in the HCl solution. All the drug releases were performed in triplicates, and the releasing percentage of the PA from drug delivery system exhibited small standard deviations, implying a good reproducibility. Nuclear magnetic resonance (NMR) results revealed that the chemical shifts of the hydrogen signals within PA showed significant changes before and after being loaded in magadiite, indicating strong interaction between the magadiite and procainamide in the Mag-PA. These studies imply that the magadiite may be a promising carrier of positively charged drugs with controlled release.