Construction of Sulfhydryl-Amino UiO-66/PVDF Membranes via Morphology Regulation for the Selective Separation of Artesunate.

Artesunate (ARU), a key derivative of artemisinin (ART), exhibits excellent water solubility and antimalarial activity due to its incorporation of a succinic acid group. However, the synthesis process of ARU often leaves behind ART with a highly similar structure and properties, making traditional separation methods ineffective for efficient separation. Developing selective separation technologies holds significant importance. Based on previous studies, in work involving the preparation of bidentate MOFs with different ligands, bidentate MOFs containing thiol/amino groups have been found to exhibit outstanding adsorption capacity and selectivity for ARU molecules. Among these, -NH2 forms hydrogen bonds with -COOH in ARU, while -SH interacts non-specifically with Aru, significantly enhancing the adsorption effect. This study employed a delayed inversion method to prepare a sulfhydryl-amino UiO-66/PVDF hybrid membrane (UiO-66-SH/NH2/PVDF) by adjusting the composition of the coagulation bath, which was used for efficient separation of ART/ARU. The effects of ethanol ratio in the coagulation bath on membrane structure and performance were systematically investigated. Results showed that increasing the ethanol ratio delays phase transition, promotes MOF material enrichment on membrane pore surfaces, and forms more abundant pore structures. When the ethanol-to-water volume ratio was 1:1, the UiO-66-SH/NH2/PVDF membrane exhibited optimal pore structure and highest water flux. Static permeation experiments demonstrated that the membrane achieved effective separation of ARU and ART for 8 h, maintaining stable selective adsorption performance after five cycles. This study reveals the critical role of morphology regulation in separating structural analogs, providing new materials and theoretical foundations for efficient separation of artemisinin-based compounds.