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.

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Facing the global health crisis caused by drug-resistant bacteria, antimicrobial peptides and their analogues offer exciting solutions to this widespread problem. Without additionally introducing a fluorescent probe, novel nanoengineered peptide-grafted hyperbranched polymers (NPGHPs) are constructed for their combined outstanding antimicrobial activity and sensitive bacterial detection in real time. Hyperbranched polyamide amine (H-PAMAM) that exhibits aggregation-induced emission (AIE) effects is synthesized. Then, NPGHPs are prepared by ring-opening polymerization of α-amino acid N-carboxyanhydrides on the periphery of the H-PAMAM. The NPGHPs exhibit high-efficiency antibacterial properties against a wide spectrum of bacteria, especially against Gram-negative bacteria. On the basis of the AIE effect of NPGHPs, the interaction between NPGHPs and Escherichia coli is explored and the fluorescence intensity of NPGHPs is dependent on the number of E. coli present. Thus, a method for monitoring E. coli concentration is developed, and the detection limit is 1 × 104 CFU mL–1. Furthermore, NPGHPs are used as fluorescent probes to visualize antibacterial process via lighting-up bacteria. NPGHPs can penetrate the membrane of bacteria and cause cell rupture and apoptosis. In addition, the excellent selectivity of NPGHPs toward bacteria over mammalian cells makes them bright prospects for clinical applications.

Biocompatible Janus composite membrane with double self‐repairing ability is constructed on the surface of magnesium, using paeonol‐doped poly(ε‐caprolactone) (P@PCL) as a hydrophobic layer and imide‐bond‐based chitosan hydrogel (PGD) as a hydrophilic layer. A copper mesh is used as the base to indirectly study this specific ability of the as‐prepared Janus membrane. The water contact angle of the Janus copper mesh‐P@PCL‐PGD with the hydrophobic layer at the bottom and the hydrophilic layer at the top is 65°, and its water retention height reached 5.1 cm, showing the strongest prevention capacity of water infiltration. Further, the damage of the hydrophobic layer is repaired by the corrosion inhibitor and the magnesium ion complex membrane; the hydrophilic layer is healed by the quick response of the imine bond in the gel to the pH change. Among all samples, the weight loss rate of Mg‐P@PCL‐PGD is found to be the smallest—only 1.19% after 12 d and 5.20% after 21 d. In short, effective protection of magnesium is achieved which is conducive to cell adhesion and proliferation, through systematically summarizing the synergy between Janus membrane and dual self‐repair. The related results are distinctive and will open up new research directions for corrosion protection of metals.

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