Here, we constructed a nanostructured pH/redox dual-responsive supramolecular drug carrier with both aggregation-induced emission (AIE) and Forster resonance energy transfer (FRET) effects, which enabled selective drug release and monitoring drug delivery and release processes. Taking the hyperbranched polyamide amine (H-PAMAM) with intrinsic AIE effects as the core, poly­(ethylene glycol) (PEG) was bridged on its periphery by dithiodipropionic acid. Then, through the host–guest interaction of PEG and α-cyclodextrin, the supramolecular nanoparticles with AIE effects were constructed to load the anticancer drug doxorubicin (DOX). The supramolecular assembly has sufficiently large DOX loading due to the abundant cavities formed by branched structures. The hyperbranched core H-PAMAM has strong fluorescence, and the dynamic track of drug carriers and the dynamic drug release process can be monitored by the AIE and FRET effects between H-PAMAM and DOX, respectively. Furthermore, the introduction of disulfide bonds and the pH sensitivity of H-PAMAM enable the achievement of rapid selective release of loaded DOX at the tumor while remaining stable under normal physiological conditions. In vitro cytotoxicity indicates that the drug-loaded supramolecular assembly has a good therapeutic effect on cancer. In addition, the H-PAMAM core is different from the traditional AIE functional group, which has no conjugated structure, such as a benzene ring, thereby providing better biocompatibility. This technology will have broad applications as a new drug delivery system.

In this work, the biodegradable and histocompatibility properties of pure Mg and ZK60 alloy were investigated as new temporary implants for urinary applications. The corrosion mechanism in artificial urine was proposed using electrochemical impedance spectroscopy and potentiodynamic polarization tests. The corrosion potential of pure magnesium and ZK60 alloy were −1820 and −1561 mV, respectively, and the corrosion current densities were 59.66 ± 6.41 and 41.94 ± 0.53 μA cm−2, respectively. The in vitro degradation rates for pure Mg and ZK60 alloy in artificial urine were 0.382 and 1.023 mm/y, respectively, determined from immersion tests. The ZK60 alloy degraded faster than the pure Mg in both artificial urine and in rat bladders (the implants of both samples are ø 3 mm × 5 mm). Histocompatibility evaluations showed good histocompatibility for the pure Mg and ZK60 alloy during the 3 weeks post-implantation in rat bladders, and no harm was observed in the bladder, liver and kidney tissues. The results provide key information on the degradation properties and corrosion mechanism of pure Mg and ZK60 alloy in the urinary system.

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