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Precisely delivering combinational therapeutic agents has become a crucial challenge for anti-tumor treatment. In this study, a novel redox-responsive polymeric prodrug (molecular weight, MW: 93.5 kDa) was produced by reversible addition–fragmentation chain transfer (RAFT) polymerization. The amphiphilic block polymer-doxorubicin (DOX) prodrug was employed to deliver a hydrophobic photosensitizer (PS), chlorin e6 (Ce6), and the as-prepared nanoscale system [NPs(Ce6)] was investigated as a chemo-photodynamic anti-cancer agent. The glutathione (GSH)-cleavable disulfide bond was inserted into the backbone of the polymer for biodegradation inside tumor cells, and DOX conjugated onto the polymer with a disulfide bond was successfully released intracellularly. NPs(Ce6) released DOX and Ce6 with their original molecular structures and degraded into segments with low MWs of 41.2 kDa in the presence of GSH. NPs(Ce6) showed a chemo-photodynamic therapeutic effect to kill 4T1 murine breast cancer cells, which was confirmed from a collapsed cell morphology, a lifted level in the intracellular reactive oxygen species, a reduced viability and induced apoptosis. Moreover, ex vivo fluorescence images indicated that NPs(Ce6) retained in the tumor, and exhibited a remarkable in vivo anticancer efficacy. The combinational therapy showed a significantly increased tumor growth inhibition (TGI, 58.53%). Therefore, the redox-responsive, amphiphilic block polymeric prodrug could have a great potential as a chemo-photodynamic anti-cancer agent.

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Tactile pressure sensing over a wide operation range (>1 MPa) is challenging for a variety of applications in fields such as aviation, oceanography, and biomedicine. Recently, innovative strategies have been utilized to improve the performances of tactile sensors using specially designed structures, dielectric layers, and electrodes. Here, a hierarchical structural design based on ionic gel films has been utilized to build iontronic pressure sensors with ultrahigh sensitivities and broad operation ranges. Sculptured patterns made by a controlled CO 2 laser scanning process have been produced on polyimide films to achieve two kinds of protrusion structures for high specific surface areas and strength to withstand high pressure. The iontronic sensor has been constructed by adding two screen-printed electrodes of high surface areas to achieve an ultrahigh sensitivity of 2593 kPa −1 and a wide pressure range from 0 Pa to 3.36 MPa. The prototype device also has a fast response and recovery time of 26 and 13 ms, respectively, and an excellent mechanical durability in the endurance test of over 2700 repeated loading and unloading cycles under a pressure of 1 MPa. Several application examples have been demonstrated, including the detection of physiological signals on human volunteers, the feedback control of intelligent robots, the grasping operation of underwater soft grippers, and the environmental wind-speed monitoring. As such, this work demonstrates a versatile and economical methodology to produce high-performance flexible sensors for various potential applications.