Biodegradable and biocompatible polyampholyte microgels derived from chitosan, carboxymethyl cellulose and modified methyl cellulose

► Two biocompatible and biodegradable polyampholyte microgels were prepared. ► The microgels were pH- and thermo-responsive. ► Microgels possessed positive and negative charges at low and high pH, respectively. ► The hydrodynamic radii were 190 nm at low pH, 80 nm at neutral pH, to 120 nm at a high pH. ► In vitro drug release studies confirmed that the microgels could encapsulate and release a model drug. ► They could potentially be used as biocompatible and biodegradable drug carriers.