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Diabetic wounds are prone to recurrent infections, often leading to delayed healing. To address this challenge, we developed a chitin-copper sulfide (CuS@CH) composite sponge, which combines bacterial trapping with near-infrared (NIR) activated phototherapy for treating infected diabetic wounds. CuS nanoparticles were synthesized and incorporated in situ within the sponge using a chitin assisted biomineralization strategy. The positively charged chitin surface effectively adhered bacteria, while NIR irradiation of CuS generated reactive oxygen species (ROS) heat and Cu 2+ to rapidly damage the trapped bacteria. This synergistic effect resulted in an exceptional antibacterial performance against E. coli (∼99.9%) and S. aureus (∼99.3%). The bactericidal mechanism involved NIR-induced glutathione oxidation, membrane lipid peroxidation, and increased membrane permeability. In diabetic mouse models, the CuS@CH sponge accelerated the wound healing of S. aureus infected wounds by facilitating collagen deposition and reducing inflammation. Furthermore, the sponge demonstrated good biocompatibility. This dual-functional platform integrating bacterial capture and NIR-triggered phototherapy shows promise as an antibacterial wound dressing to promote healing of infected diabetic wound.

Traditional packaging materials feed the growing global food protection. However, these packaging materials are not conducive to environment and have not the ability to kill bacteria. Herein, a green and simple strategy is reported for food packaging protection and long-term antibacterial using carboxymethylcellulose-based photothermal film (CMC@CuS NPs/PVA) that consists of carboxymethyl cellulose (CMC) immobilized copper sulfide nanoparticles (CuS NPs) and polyvinyl alcohol (PVA). With satisfied oxygen transmittance (0.03 cc/m 2 /day) and water vapor transmittance (163.3 g/m 2 /day), the tensile strength, tear strength and burst strength reached to 3401.2 N/m, 845.7 mN and 363.6 kPa, respectively, which could lift 4.5 L of water. The composite film had excellent photothermal conversion efficiency and photothermal stability. Under the irradiation of near infrared (NIR), it can rapidly heated up to 197 °C within 25 s. The antibacterial analysis showed that the inhibition rate of composite film against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) could all reach >99 %. Furthermore, the synthesized CuS NPs was well immobilized and the residual rate of copper kept 98.7 % after 10 days. Noticeably, the composite film can preserve freshness of strawberries for up to 6 days. Therefore, the composite film has potential application for food antibacterial protection., 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 B.V. All rights reserved.)

In this study, novel Cu-complexes of heterocyclic cellulose which were synthesized via the reaction of carboxymethyl cellulose (CMC) from bagasse pulp with NH 2 NH 2 to give hydrazide cellulose which easily reacted with CS 2 to form salt and then cyclized in the presence of HCl to afford cellulose oxadiazole, or with hydrazine hydrate to give cellulose triazole. Furthermore, the cellulose oxadiazole and triazole moieties acting as chelating agents with metal ion Cu (II), and all synthesized compounds were examined for their spectral analysis to show the adsorption of Cu (II) on the surface of cellulose through intramolecular hydrogen bonding. Results illustrated that cellulose oxadiazole and Cu- cellulose oxadiazole exhibited antimicrobial activities more than triazole and Cu- cellulose triazole. Furthermore, anticancer results showed that both cellulose oxadiazole and triazole exhibited activity higher than Cu-cellulose oxadiazole and Cu-cellulose triazole, where the cellulose triazole showed the highest activity (IC50 = 58.7 μg/μL). Additionally, the docking simulation of the synthesized cellulose complexes with different proteins such as PDBID:3t88, PDBID:4ynt, PDBID:1tgh, PDBID:2wje, and PDBID:4hdq and shortage bond length to confirm the experimental results. Optimization of metal complexes utilized the DFT/B3LYP/LANL2DZ basis set to confirm the stability of these metals theoretically and their physical descriptors and FMO analysis., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Improving electron transfer rate of Co species and inhibiting aggregation of metal-organic frameworks (MOFs) particles are essential prerequisites for activating advanced oxidation process in wastewater treatment field. Here, we exploit Cu species with variable valence states to accelerate electron transfer of Co species and then to boost the unsatisfactory degradation efficiency for refractory pharmaceuticals via in-situ growth of copper and cobalt species on l-lysine functionalized carboxylated cellulose nanofibers. Utilizing the synergistic interplay of Co sites and deliberately exposed Cu 0 /Cu 1+ atoms, the subtly designed catalyst exhibited a surprising degradation efficiency (~100 %) toward tetracycline hydrochloride within 10 min (corresponding to a catalytic capacity of 267.71 mg/g) without adjusting temperature and pH. Meanwhile, the catalyst displays good recyclability, well tolerance for coexisting ions and excellent antibacterial performance derived from the intrinsic antibacterial property of Cu-MOF. This research provided a novel strategy to construct MOFs-cellulose materials toward degrading various stubborn antibiotic pollutants., 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 B.V. All rights reserved.)

The quality of wine can be affected by excess Cu 2+ due to the occurrence of oxidation reactions or precipitation. Therefore, it is essential to use simple and effective testing methods to ensure the Cu 2+ content in wine. In this work, we designed and synthesized a rhodamine polymer fluorescent probe (PEG-R). The water solubility of PEG-R was improved by the introduction of polyethylene glycol, which improved the performance and broadened its application in the food field. The PEG-R was characterized by high sensitivity, selectivity and fast response to Cu 2+ and was able to complete the response process within 30 s, with approximately 29-fold fluorescence enhancement of the probe after exposure to Cu 2+ , the limit of detection (LOD) was 1.295 × 10 -6 M. The probe can be used for the determination of Cu 2+ in living cells, zebrafish, white wine and food products, and it was made into practical gels and test strips., 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 Elsevier Ltd. All rights reserved.)