Preparation, Characterization, and Gastric Mucosal Cell Migration Promotion of EGCG Nanoparticles Released from a Low pH Environment

(−)-Epigallocatechin-3-gallate (EGCG), as the primary bioactive constituent of tea, exhibits potential health benefits and therapeutic effects on the gastrointestinal system. However, its application is limited by its instability within the gastrointestinal tract, as well as its low systemic delivery efficiency and poor oral bioavailability. This study developed EGCG nanoparticles using bovine serum albumin (BSA) and dextran. Optimal parameters (VEGCG/VBSA/VDextran = 1:2:2) produced nanoparticles with high encapsulation efficiency (94.31%), uniform size (597.04 ± 12.6 nm), stable zeta potential (−24.63 ± 0.85 mV), and favorable morphological characteristics. These nanoparticles exhibited sustained-release properties in vitro and significant antioxidant capacity under simulated gastrointestinal conditions. Notably, they enhanced the migration of gastric epithelial cells under acidic conditions (pH 4.5). The developed nanoformulation strategy effectively addresses critical challenges in EGCG delivery by improving controlled release kinetics and promoting gastric mucosal repair mechanisms in low pH environments.