Biodegradable polyanhydrides possess unique features like those that they can predominantly undergo
surface erosion, and the payloads can be released by a steady speed. However, there is little work that has
been published to describe the polyanhydride micelles with redox-responsiveness as a nanocarrier for
drug delivery. In this study, we develop one type of new amphiphilic polyanhydride copolymer containing
disulfide bonds between the hydrophilic and hydrophobic segments. The copolymer can selfassemble
into stable micelles with well-defined coreeshell structure and a uniform size distribution
with an average diameter of 69 nm. The disassembly behaviors of the micelles triggered by glutathione
are evaluated from the changes of the micellar size, morphology and molecular weight. An approximate
zero-order in vitro drug release mode with a fast speed can be achieved in a reducing and acid environment
similar with that of tumor cells. In vitro cytotoxicity analysis demonstrate that the Cur-loaded
micelles are of great efficiency in inhibiting the growth of cancer cells due to the rapidly intracellular
delivery of therapeutic agent. Both the qualitative and quantitative results of the antitumor activity in
4T1 tumor-bearing BALB/c mice reveal that the redox-responsive micelles have a more significant
therapeutic effect to artificial solid tumor compared to the redox-insensitive micelles. This study provides
a new insight into the biomedical application of polyanhydrides in drug delivery.


Jie Wang,Guang Yang,Xing Guo,Zhaomin Tang,Zhendong Zhong,Shaobing Zhou.