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Concern about food safety triggers demand on rapid, accurate and on-site detection of foodborne pathogens. Among various fluorescent probes for detection, carbon dots (CDs) prepared by carbonization of carbon-rich raw materials show extraordinary performance for their excellent and tailorable photoluminescence property, as well as their facilely gained specificity by surface customization and modification. CDs-based fluorescent probes play a crucial role in many pathogenic bacteria sensing systems. In addition, microfluidic technology with characteristics of portability and functional integration is expected to combine with CDs-based fluorescent probes for point-of-care testing (POCT), which can further enhance the detection property of CDs-based fluorescent probes. Here, this paper reviews CDs-based bacterial detection methods and systems, including the structural modulation of fluorescent probes and pathogenic bacteria detection mechanisms, and describes the potential of combining CDs with microfluidic technology, providing reference for the development of novel rapid detection technology for pathogenic bacteria in food., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The purpose of this study was to enhance the antimicrobial activity of bagasse paper by coating the paper with bismuth oxide (Bi 2 O 3 ) and using it to accelerate the process of wound healing. Paper sheets were prepared from sugarcane waste (bagasse). First, the paper sheets were coated with different Bi 2 O 3 concentrations to improve the antimicrobial activity of the paper. After that, the paper sheets were allowed to dry in an oven at 50 °C for 3 h. Then, in vitro antimicrobial activity was evaluated against different microbial species, including Gram-negative bacteria (i.e., Klebsiella pneumonia, Escherichia coli) and Gram-positive bacteria (i.e., Staphylococcus aureus, Streptococcus pyogenes). The obtained results showed that the paper coated with 25% and 100% Bi 2 O 3 had activity against all models of bacteria; however, the paper coated with 100% Bi 2 O 3 composite had the strongest inhibitory effect. Then, bagasse paper was coated with 100% Bi 2 O 3 and different antibiotics, to investigate their wound-healing potency in a wounded rat model for 14 days. Moreover, the paper coated with 100% Bi 2 O 3 inhibited the cellular migration in vitro. Conclusively, coating paper with Bi 2 O 3 enhances the wound-healing potential when applied to wounds. This impact could be ascribed to Bi 2 O 3 's broad antibacterial activity, which reduced infection and accelerated the healing process.

Electromagnetic (EM) pollution has become a serious problem in modern society as it affects human lives. The fabrication of strong and highly flexible materials for electromagnetic interference (EMI) shielding applications is extremely urgent. Herein, a MXene Ti 3 C 2 T x /Fe 3 O 4 & bacterial cellulose (BC)/Fe 3 O 4 &Methyltrimethoxysilane (MTMS) flexible hydrophobic electromagnetic shielding film (SBTF X-Y , X and Y were the number of layers of BC/Fe 3 O 4 and the layers of Ti 3 C 2 T x /Fe 3 O 4 ), was fabricated. In the prepared film, MXene Ti 3 C 2 T x absorbs a large amount of radio waves through polarization relaxation and conduction loss. Because of its extremely low reflectance of electromagnetic waves, BC@Fe 3 O 4 , as the outermost layer of the material, allows more electromagnetic waves to incident inside the material. The maximum electromagnetic interference (EMI) shielding efficiency (SE) of 68 dB was achieved for the composite film at 45 μm thickness. What's more, the SBTF X-Y films show excellent mechanical properties, hydrophobicity and flexibility. The unique stratified structure of the film provides a new strategy for designing high-performance EMI shielding films with excellent surface and mechanical properties., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Modification of kraft lignin (KL), traditionally uses harsh and energy-demanding physical and chemical processes. In this study, the potential of the bacterial laccase CotA (spore coating protein A) for oxidation of KL under mild conditions was assessed. Thereby, the efficiency of CotA to oxidize both softwood and hardwood KL of varying purity at alkaline conditions was examined. For the respective type of wood, the highest oxidation activity by CotA was determined for the medium ash content softwood KL (MA_S) and the medium ash content hardwood KL (MA_H), respectively. By an up to 95% decrease in fluorescence and up to 65% in phenol content coupling of the structural lignin units was indicated. These results correlated with an increase in viscosity and molecular weight, which increased nearly 2 and 20-fold for MA_H and about 1.3 and 6.0-fold for MA_S, respectively. Thus, this study confirms that the CotA laccase can oxidize a variety of KL at alkaline conditions, while the origin and purity of KL were found to have a major impact on the efficiency of oxidation. Under the herein tested conditions, it was observed that the MA_H KL showed the highest susceptibility to CotA oxidation when compared to the other hardwood KLs and the softwood KLs. Therefore, this could be a viable method to produce sustainable resins and adhesives.