Surface-Engineered Magnesium Metal–Organic Frameworks for Curcumin Stabilization: Interfacial Coordination Enhances Aqueous Stability and Boosts Antioxidant Efficacy 32-Fold

Abstract

Curcumin possesses exceptional therapeutic and antioxidant potential, yet its clinical translation remains severely bottlenecked by rapid hydrolytic degradation and poor stability in aqueous environments. Herein, we report a robust and highly efficient magnesium-based metal–organic framework (MgMOF) platform designed to encapsulate and stabilize curcumin via a facile wet impregnation strategy. Systematic optimization of processing parameters─including kinetics, thermodynamics, and mass ratios─revealed that a 1 h stirring regime with a 1:4 MgMOF-to-curcumin molar ratio yields a superior loading capacity of 46 wt % while preserving the long-range crystalline order of the host framework. Comprehensive structural and physiochemical characterization utilizing thermogravimetric analysis, powder X-ray diffraction, scanning electron microscopy, and Fourier-transform infrared spectroscopy confirmed successful surface adsorption driven by specific coordination interactions between the curcumin functional groups and the open Mg2+ coordination centers. Crucially, the MgMOF-curcumin conjugate demonstrated a 4-fold reduction in the curcumin degradation rate, maintaining structural integrity over an extended 10-day period in aqueous media. Furthermore, 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays revealed that the host matrix not only preserves but also synergistically boosts bioactivity, culminating in an unprecedented 32-fold enhancement in antioxidant efficacy at physiologically relevant neutral pH compared to free curcumin. These findings highlight the potential of MgMOFs as biomaterial carriers to overcome the intrinsic limitations of hydrophobic bioactives, paving the way for advanced pharmaceutical and targeted therapeutic delivery systems.