There is an urgent need for developing novel strategies for bacterial detection and inhibition. Herein, a multifunctional nanomaterial based on mesoporous silica nanoparticles (MSNs) is designed, loaded with amoxicillin (AMO), and surface-coated with 1,2-ethanediamine (EDA)-modified polyglycerol methacrylate (PGEDA), cucurbit[7]uril (CB[7]), and tetraphenylethylene carboxylate derivatives (TPE-(COOH)) by the layer-by-layer (LbL) self-assembly technique. When bacteria contacts with this nanoassembly, the binding of anionic bacterial surface toward the cationic PGEDA layer of this material can reduce or break the interactions between PGEDA layer and TPE-(COOH) layer, leading to attenuated TPE-(COOH) emission due to the weakening of aggregation-induced emission (AIE) effect. Furthermore, upon adding adamantaneamine (AD), the more stable AD⊂CB[7] complex forms and PGEDA is liberated through competitive replacement, thus leading to the release of AMO and resulting in much higher antibacterial ability of this nanomaterial. This newly designed nanomaterial possesses dual functions of controllable antibacterial activity against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli, and bacterial detection ability in aqueous media, suggesting that the design of this multifunctional antibacterial material will provide a simple, effective, and rapid way to control the activity of antimicrobial and open up an alternative new avenue for bacterial detection and elimination.

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Light-stimulated AIE-based nanocomplexes have been developed as convenient tools to accomplish the tasks of the detection and inhibition of bacteria.

Bacterial infections have been considered to be one of the greatest threats to human health. In this study, a covalently cross-linked GO membrane was fabricated through vacuum-assisted filtration self-assembly after being consequentially functionalized with dopamine (GO-PDA) and branched polyethylenimine (GO-PDA-PEI). The characteristics of GO, GO-PDA, and GO-PDA-PEI membranes were confirmed by Xray diffraction, Fourier transform infrared measurements, scanning electron microscopy images, static water contact angle measurements, etc. The GO-PDA-PEI membrane showed extraordinary stability, compared with GO and GO-PDA, confirmed by ultrasonication treatment. Notably, the GO-PDA-PEI membrane exhibited excellent antibacterial efficiency for both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli (more than 99%) upon irradiation by a 795 nm near-infrared (NIR) laser. Interestingly, the GO-PDA-PEI membrane can be recycled, that is, the photothermal effect, as well as the antibacterial activity of the GO-PDA-PEI membrane, remained the same after 5-time recycling. Hence, the proposed system has great potential for future design of recyclable, highly stable, superior bacteriostatic membrane materials.

This study aims to evaluate the laboratory safety perception, awareness and attitude of undergraduates toward the chemistry teaching laboratory by means of a self-administered questionnaire. The survey contains a sample size of 959 undergraduates in Tianjin University of Technology involving four schools. Instrument reliability and validity are also tested. The results show that most of the students have a more positive laboratory environmental perception and safety awareness. However, the laboratory safety attitude needs improvement. In addition, there is a significant difference for both gender and school. This result could lead to the improvement of the subsequent safety education.