Fig. 4
(Reproduced with permission from [146]. © 2021 Elsevier B.V. All rights reserved)
pH-sensitive hydrazone bonds attached doxorubicin to mPEG-based diblock copolymers. a Rates of Doxo release from different ratios of Leu and Glu copolymers bound to mPEG at varying pH conditions; Doxo release profile of mPEG5kDa-(Doxo-hydGlu)16; b Doxo release profile of mPEG5kDa-b-[(Dox-hydGlu)6-r-Leu10]; c Confocal microscopy images of CT26 cells and nanodrug after 2Â h incubation and a further 4Â h incubation. Nanodrug delivery into the cells and cleavage of the hydrazone bond in an acidic lysosomal environment resulted in Doxo release