A pH dependent thermo-sensitive copolymer drug carrier incorporating 4-amino-2,2,6,6-tetramethylpiperidin-1-oxyl (4-NH2-TEMPO) residues for electron spin resonance (ESR) labeling

► A pH dependent thermo-sensitive copolymer with narrow window of LCST was synthesized. ► The CMC of micelles was corresponded to 4.0523 mg/L. ► The situation of TEMPO carrying micelles can be detected by ESR. ► The micelles showed non-toxicity towards cells, pointed to their biocompatibility.