Unique Short Title: "pH-Responsive Nano-Hydrogel Carrier for Controlled Albumin Delivery" Rewritten Abstract: A novel nano-covalent hydrogel was synthesized for pH-modulated protein delivery. The polymer, formed from phthalic anhydride and glycerol and cross-linked with acrylic acid, exhibited nanoscale architecture (~68 nm) and pH-dependent swelling. Albumin loading and release were significantly enhanced in alkaline environments (pH 8.0) compared to acidic conditions (pH 2.2), with optimized release occurring over six hours. This tunable, pH-sensitive system demonstrates potential for targeted drug delivery in physiological regions with elevated pH, supporting its application in advanced, responsive therapeutic carriers.