Green Tea Catechin@ZIF-8 Encapsulation within Calcium Alginate Hydrogel: Preparation, Characterization and <i>In-Vitro</i> Release

Catechins, naturally derived from green tea leaves, are potent antioxidants known for their anti-inflammatory, antimicrobial, anticancer, cardiovascular, and antidiabetic properties. In this study, green tea catechin was successfully encapsulated within a zeolitic imidazolate framework-8 (cate@ZIF-8) and further incorporated into a calcium alginate hydrogel to improve its stability and bioavailability. The system's encapsulation efficiency, structural properties, and release behavior were comprehensively analyzed. X-ray diffraction (XRD) confirmed that the crystalline structure of ZIF-8 remained intact after catechin encapsulation, while Fourier transform infrared spectroscopy (FT-IR) indicated specific interactions between catechin molecules and the ZIF-8 framework. Scanning electron microscopy (SEM) was employed to examine the morphology of the cate@ZIF-8 particles within the alginate hydrogel matrix. Catechin release studies under different pH conditions demonstrated a controlled release profile, especially in acidic environments. These findings underscore the potential of alginate-embedded cate@ZIF-8 hydrogels as an effective platform for sustained catechin delivery in therapeutic applications.