Release dynamics and toxicological analysis of astilbin from lauric acid/BSA-coated superparamagnetic iron oxide...

The research was designed to analyze the in vitro drug release kinetics of astilbin (AST)-loaded lauric acid (LA)/bovine serum albumin (BSA)-coated superparamagnetic iron oxide nanoparticles (SPION^LA/BSA) as drug delivery vehicles for cholangiocarcinoma (CCA) therapy. Specifically, the study aimed to determine the diffusion coefficient of AST (D) and the dissolution rate (k'a) of the drug, as well as to assess the in vitro cytotoxicity against KKU-055 and KKU-213. The in vitro drug release profiles of AST-loaded SPION^LA/BSA demonstrated their potential for a targeted and pH-sensitive delivery mechanism. The AST release profile at different concentrations (10, 15, 20, and 25 ppm) was best fitted by the Korsmeyer-Peppas model. The release exponents (n ≤ 0.45) indicated that the drug release mechanism was controlled by quasi-Fickian diffusion. The control of drug release dynamics of AST predicted using a combination of the Noyes-Whitney and Fick's second law, was best described by a second-order release-rate diffusion control at a 10 ppm loading concentration. In contrast, a higher initial concentration (20 ppm) was best described by a first-order release-rate diffusion control model. In the cytotoxicity studies, SPION^LA/BSA demonstrated a greater decrease in cell viability compared to uncoated-SPION, in a dose-dependent manner (0-150 μg·cm^-3). After 48 h of treatment, KKU-213 cells exhibited the highest cell growth inhibition, with a 54.73 % reduction in viability compared to the control group. These findings suggest that AST has potential as a potent anticancer agent for inhibiting CCA cell growth, while SPION^LA/BSA shows promise as an effective carrier for anticancer drug delivery.