A new nano-antibacterial strategy based on a biodegradable charge-transfer nanocomplex (CTN) was developed, in which the CTN acted as a high-efficiency near-infrared light-activatable photothermal nanoconvertor.

As one of the nanostructures with enzyme-like activity, nanozymes have recently attracted extensive attention for their biomedical applications, especially for bacterial disinfection treatment. Nanozymes with high peroxidase activity are considered to be excellent candidates for building bacterial disinfection systems (nanozyme-H2O2), in which the nanozyme will promote the generation of ROS to kill bacteria based on the decomposition of H2O2. According to this criterion, a cerium oxide nanoparticle (Nanoceria, CeO2, a classical nanozyme with high peroxidase activity)-based nanozyme-H2O2 system would be very efficient for bacterial disinfection. However, CeO2 is a nanozyme with multiple enzyme-like activities. In addition to high peroxidase activity, CeO2 nanozymes also possess high superoxide dismutase activity and antioxidant activity, which can act as a ROS scavenger. Considering the fact that CeO2 nanozymes have both the activity to promote ROS production and the opposite activity for ROS scavenging, it is worth exploring which activity will play the dominating role in the CeO2-H2O2 system, as well as whether it will protect bacteria or produce an antibacterial effect. In this work, we focused on this discussion to unveil the role of CeO2 in the CeO2-H2O2 system, so that it can provide valuable knowledge for the design of a nanozyme-H2O2-based antibacterial system.

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Efficiently and spatiotemporally controllable cleavage of deoxyribonucleic acid (DNA) is of great significance both for disease treatment (e.g. tumour, bacterial infection, etc) and molecular biology applications (e.g. gene editing). The...

In this work, the single variable method is used to investigate the effect of various laser parameters on the diameter, taper, and the quality of the through hole when silicon holes are machined with a 355 nm all-solid-state UV laser. Studies have shown that with an increase of laser fluence, the resolidification at the hole edge is alleviated, and the hole diameter increases slightly with it. The high repetition frequency aggravates the recasting on the hole walls and edges, and the hole taper is also increased due to the high repetition frequency. Excessive scanning speed causes the hole wall to be uneven and results in a large amount of melt attached to the sidewall. However, in case the scanning speed is too slow, the quality of the hole deteriorates due to severe heat accumulation. With proper negative defocus distance, the through hole with a relatively smooth sidewall and a small taper can be obtained. The results provide a technological reference for processing high quality through silicon holes by a 355 nm all-solid-state UV laser.