Semiconductor nanomaterials with photocatalytic activity have potential for many applications. An effective way of promoting photocatalytic activity is depositing noble metal nanoparticles (NPs) on a semiconductor, since the noble metal NPs act as excellent electron acceptors which inhibit the quick recombination of the photoexcited electron-hole pairs and thereby enhance the generation of reactive oxygen species (ROS). Herein, a highly effective platform, graphitic carbon nitride (g-C₃N₄) nanosheets with embedded Ag nanoparticles (Ag/g-C₃N₄), was synthesized by a facile route. Under visible light irradiation, the ROS production of Ag/g-C₃N₄ nanohybrids was greatly improved compared with pristine g-C₃N₄ nanosheets, and moreover, the nanohybrids showed enhanced antibacterial efficacy and ability to disperse bacterial biofilms. We demonstrate for the first time that the Ag/g-C₃N₄ nanohybrids are efficient bactericidal agents under visible light irradiation, and can also provide a new way for biofilm elimination. The enhanced antibacterial properties and biofilm-disrupting ability of Ag/g-C₃N₄ nanohybrids may offer many biomedical applications.

Marine fouling is a worldwide problem, which is harmful to the global marine ecological environment and economic benefits. The traditional antifouling strategy usually uses toxic antifouling agents, which gradually exposes a serious environmental problem. Therefore, green, long-term, broad-spectrum and eco-friendly antifouling technologies have been the main target of engineers and researchers. In recent years, many eco-friendly antifouling technologies with broad application prospects have been developed based on the low toxicity and non-toxicity antifouling agents and materials. In this review, contemporary eco-friendly antifouling technologies and materials are summarized into bionic antifouling and non-bionic antifouling strategies (2000–2020). Non-bionic antifouling technologies mainly include protein resistant polymers, antifoulant releasing coatings, foul release coatings, conductive antifouling coatings and photodynamic antifouling technology. Bionic antifouling technologies mainly include the simulated shark skin, whale skin, dolphin skin, coral tentacles, lotus leaves and other biology structures. Brief future research directions and challenges are also discussed in the end, and we expect that this review would boost the development of marine antifouling technologies.

GO-NTA-Ce has DNase-like enzyme properties and excellent photothermal effect. The combination of photothermal treatment with chemical degradation and physical destruction can completely kill bacteria encased in biofilms.

Herein, we employed the hydrogen-producing hyperthermophilic bacterial strain Caldicellulosiruptor changbaiensis for preparing uniform and size-tunable gold nanoparticles (AuNPs). Compared with the commonly used chemically synthesized nanoparticles, the biological synthesis of nanoparticles appears to be a suitable process since it has a low manufacturing cost of scalability, good biocompatibility, and better nanoparticles stabilization. The produced AuNPs possessed a unique property, whereby the smallest AuNPs exhibited the highest peroxidase activity over a broad pH range, even at neutral pH, which was quite different from the commonly chemical-synthesized ones. Also, when the size of AuNPs increased, the peroxidase activity of B-AuNPs at neutral pH decreased. Owing to the excellent antibacterial capability of ROS, the AuNPs exhibited striking antibacterial properties against both Gram-positive and Gram-negative bacteria, and moreover, the AuNPs showed excellent ability to disperse bacterial biofilms both in vitro and in vivo. Our studies indicate that living bacterial cells, as a biosynthesizer, can synthesize size-controllable AuNPs with improved bioactivity. This work may promote the design and synthesis of other types of metal nanoparticles with defined properties for future applications.

H ₂ O ₂ -free depots (CaO ₂ /H-G@alginate) can produce hROS in situ through localized cascade reactions, damaging the main components of biofilms.