pH-Responsive Hydrogels

MARIA REGATO; JUAN MARTÍN GIUSSI; SERGIO MOYA

Hydrogels for Tissue Engineering and Regenerative Medicine, First Edition

Elsevier

Año: 2023;

There are two types of pH responsive hydrogels: cationic hydrogels displaying amines, usually primary or tertiary, which get charged at acidic pH; and anionic hydrogels usually displaying carboxylate groups, which become charged at basic pH. In this review we revise different aspects of the synthesis and physical chemistry of both types of hydrogels. Both cationic and anionic hydrogels can be prepared from synthetic and natural polymer networks containing basic or acidic groups in the chains. This chapter is organized according to the nature of the charge of the hydrogel, which also defines the range of pH at which the hydrogel swells, with positively charged hydrogels swelling at low pH, and negatively charged hydrogels at high pH.