Pharmacokinetics study on mesoporous silica-captopril controlled release systems

The design and development of new drug delivery systems with the aim of enchancing the efficacy of existing commercialized formulations represent an ongoing process in the pharmaceutical research. Captopril, an angiotensin converting enzyme inhibitor, was successfully loaded into unfunctionalized and functionalized mesoporous silica matrices. Pharmacokinetic evaluations were performed and UV-Vis and HPLC analysis were used in order to determine the plasma concentration of the released captopril. The following pharmacokinetic parameters were evaluated: time to the maximum concentration (T_max), maximum value of plasma concentration, C_max (μg/mL), half life (T_1/2, h), area under curve AUC_0-72 (μg h/mL). Pharmacokinetics experiments evidenced that temperature conditions for drug loading and chemical nature of silica surface are determining factors in the bioavailability of the loaded substance and directly influence the overall pharmacokinetics. Additionally, the toxicity of the obtained systems was evaluated using Kärber method. The tested silica-captopril formulations may be considered attractive controlled release systems, potentially offering better bioavailability and other benefits, compared to the commercial formulation.