Engineering anisotropic wettability in metal–organic framework composites for advanced multiphase-interfacial biocatalysis

Abstract

There is an urgent need to develop high-performance immobilized enzymes for liquid–liquid reactions. However, achieving efficient reactions remains challenging due to poor control over immiscible phase collisions and reduced catalytic activity after immobilization. Additionally, separating products from the reaction mixture is difficult. To address these issues, we developed a novel enzyme immobilization strategy using Janus Au/UiO-66-TDPA (n-tetradecylphosphonic acid) metal-organic frameworks (MOFs) with anisotropic wettability as carriers, thereby enhancing biphasic reaction kinetics. Hydrophobic TDPA-modified UiO-66 and hydrophilic AuNPs ensure outstanding interfacial stability at the oil–water interface. Candida rugosa lipase (CRL) was encapsulated within the MOF channels via competitive coordination. The Janus carrier exhibits a perforated channel structure and photothermal property. Its hydrophobic/hydrophilic microenvironment enriches substrates from both phases, promoting enzyme–substrate interactions and enabling rapid product separation based on solubility differences. The photothermal effect locally elevates reaction temperatures, boosting catalytic activity while protecting the enzyme from thermal inactivation. Consequently, this system demonstrates superior performance compared to traditional methods, substantially accelerating triglyceride hydrolysis in both static and continuous-flow systems. This study paves the way to rationally design Janus-structured MOFs for enzyme immobilization across various applications.