A pH-responsive soy flour–montmorillonite–magnesium oxide complex for controlled release of curcumin in antidiabetic therapy

Abstract This study presents a pH-responsive, intestine-targeted, sustained-release curcumin delivery system based on a soy flour (SF) matrix reinforced with montmorillonite (MMT) and magnesium oxide (MgO), and crosslinked using glutaraldehyde (GA). The system addresses the limitations of curcumin’s poor solubility and instability in gastric conditions while offering a biopolymer-based alternative to conventional enteric coating strategies. The incorporation of MMT, MgO, and GA modulated encapsulation efficiency, matrix rigidity, and release rate, enabling optimisation of drug loading and sustained intestinal release. The optimised formulation demonstrated suppressed curcumin release in acidic medium (pH 1.2) and controlled prolonged release at pH 7.4, following anomalous (non-Fickian) transport. FTIR, XRD, and FESEM analyses confirmed uniform curcumin incorporation and structural reinforcement within the SF matrix. MTT assays verified high biocompatibility at low-to-moderate dopant levels, while 2-NBDG uptake studies demonstrated enhanced cellular glucose uptake, supporting the antidiabetic relevance. Overall, the findings highlight the potential of SF-based hybrid nanocomposites as a sustainable platform for controlled intestinal drug delivery in diabetes management.