Design of tough and functional hydrogel based on carbohydrate polymers is always attracting. Injectable hydrogel based on polyvinyl alcohol (PVA) and sodium alginate (Alg) have great potential for wound repair. However, simple hydrogel lacks functionality, such as antibacterial, which limits its application. Herein, we proposed a strategy of using Ag@MXene nanozyme to functionalize hydrogel and construct a near-infrared laser (NIR) responsive, reactive oxygen species (ROS) generating, and antibacterial platform for wound repair. Epigallocatechin gallate (EGCG) and Ag cluster modified Ti 3 C 2 (E-Ag@Ti 3 C 2 ) was prepared to enhance the performance of injectable PVA-alginate hydrogel (E-Ag@Ti 3 C 2 @H). The functionalized hydrogel presents porous structures (67 % porosity percentage) and excellent compressive and tensile properties (elongation up to 157 %). Under NIR laser irradiation, E-Ag@Ti 3 C 2 @H showed photothermal conversion efficiency and ROS generation ability. The inhibition rate for Methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli ( E. coli ) can reach to 91.2 % and 90.3 %, respectively. Molecular biology experiments showed that the composite hydrogel could promote angiogenesis and wound healing by upregulating the expression of anti-inflammatory factors. The obtained injectable E-Ag@Ti 3 C 2 @H hydrogel is potential in accelerating diabetic wound healing.
Yiqian Kong,Zongyi Li,Qi Liu,Juncheng Song,Yinghua Zhu,Jinping Lin,Lili Song,Xiangyang Li
In this work, V 2 C Mxene nano-enzyme materials (V 2 C MNs) with excellent peroxidase-like activity and fluorescence quenching performance were prepared, and it was modified using 6-carboxyfluorescein-labelled aptamers (ssDNA-FAM) to construct a novel dual-mode sensor V 2 C@ssDNA-FAM, with detection limits of 0.0477 ng mL −1 and 0.2789 ng mL −1 of fluorescence (linear range of 0.1–550 ng mL −1 ) and colorimetric (linear range of 1–1000 ng mL −1 ) modes, respectively. Meanwhile, an ANN intelligent detection platform has been constructed, which could automatically track and analyze the fluorescence and colorimetric signal of the detection system through machine learning and immediately obtain the AFB 1 concentration, and the detection limits of the fluorescence (linear range of 0.1–500 ng mL −1 ) and colorimetric (linear range of 1–800 ng mL −1 ) channels of it were 0.0905 ng mL −1 and 0.6845 ng mL −1 , respectively. The recovery rates of fluorescence, colorimetric sensing detection and ANN-assisted fluorescence and colorimetric sensing detection of real samples ranged from 95.40% to 101.76%. The method constructed in this work was superior to most existing literature reports and had great potential for application in the field of food quality testing.
Anticancer nanomedicines used for ferroptosis therapy generally rely on the direct delivery of Fenton catalysts to drive lipid peroxidation in cancer cells. However, the therapeutic efficacy is limited by the ferroptosis resistance caused by the intracellular anti-ferroptotic signals. Herein, we report the intrinsic ATPase-mimicking activity of a vanadium carbide MXene nanozyme (PVCMs) to pharmacologically modulate the nuclear factor erythroid 2-related factor 2 (Nrf2) program, which is the master anti-ferroptotic mediator in the ironclad defense system in triple-negative breast cancer (TNBC) cells. The PVCMs perform high ATPase-like activity that can effectively and selectively catalyze the dephosphorylation of ATP to generate ADP. Through a cascade mechanism initiated by falling energy status, PVCMs can powerfully hinder the Nrf2 program to selectively drive ferroptosis in TNBC cells in response to PVCMs-induced glutathione depletion. This study provides a paradigm for the use of pharmacologically active nanozymes to moderate specific cellular signals and elicit desirable pharmacological activities for therapeutic applications.
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