Acid-Induced Self-Catalyzing Platform Based on Dextran-Coated Copper Peroxide Nanoaggregates for Biofilm Treatment

Abstract

Nanoantibacterial agents based on catalytic activity were limited due to the low levels of endogenous H 2 O 2 in the microenvironment of bacterial biofilms. However, the additional H 2 O 2 will trigger more side effects to healthy surroundings, which is still a great challenge. Herein, we report an acid-induced selfcatalyzing platform based on dextran-coated copper peroxide nanoaggregates (DCPNAs) for antibiofilm and local infection therapy applications. The dextran-functionalized DCPNAs were mediated and conveniently purified via a dextran and ethanol precipitation method, which can also cluster nanodots into nanoaggregates and show good penetrability as well as biocompatibility. Bacterial biofilms were inhibited and destroyed by the reactive oxygen species generated from the Fenton reaction between the Cu 2+ and H 2 O 2 released from DCPNAs in an acidic environment, which did not require additional H 2 O 2 . As expected, the DCPNAs exhibit low cytotoxicity and excellent acid-induced antibacterial and antibiofilm ability. Moreover, the DCPNAs realized great therapeutic outcomes in the application for in vivo wound healing. The overall excellent properties associated with the DCPNAs highlight that they could be considered as a kind of ideal antimicrobial agents for microbial biofilm infection treatment.

Copper Peroxide Nanodots Encapsulated in a Metal–Organic Framework for Self-Supplying Hydrogen Peroxide and Signal Amplification of the Dual-Mode Immunoassay

“…At the same time, the distinct peaks of C, O, N, and Cu were observed in XPS spectra of CPNs (Figure S3A), also demonstrating the presence of PVP in CPNs. Additionally, two peaks at 953.6 and 934.5 eV could be assigned to Cu 2p 1/2 and Cu 2p 3/2 accompanied by two satellite peaks at 962.4 and 943.1 eV, respectively, indicating that the valence state of copper in PVP-CPNs was divalent, which was consistent with the previous study (Figure C) . Moreover, Figure S3B depicts that the binding energies of 530.7 and 532.5 eV were attributed to CO and O–O, respectively, signifying the existence of PVP and peroxo groups in CPNs.…”

“…The synthesis of CPNs was referred to previously reported methods. , In brief, CuCl 2 ·2H 2 O (25 mL, 0.01 M) and polyvinyl pyrrolidone (PVP, 2.5 g) were mixed in an aqueous solution at room temperature. Then, NaOH (25 mL, 0.02 M) and H 2 O 2 (500 μL, 10 M) were consecutively added into the above mixture solution.…”

“…As an alternative, metal peroxide nanoparticles (MPNs), composed of metal ions and peroxide groups, have been applied as promising candidates for self-supplying H 2 O 2 , − which showed good tolerance in response to the matrix at harsh reaction conditions in the immunoassay. , For example, CaO 2 , possessing a high capacity of self-supplying H 2 O 2 and O 2 , was employed to develop a novel luminol electrochemiluminescence (ECL) sensing platform for detecting the biomarkers of squamous cell carcinomas . Even so, MPNs used in detection systems could cause poor sensitivity of the assay due to (i) a limited amount of the signal molecule (CPN) loading and (ii) the low local concentration caused by the diffusion of self-produced H 2 O 2 . ,, …”

COVID-19-inspired “artificial virus” to combat drug-resistant bacteria by membrane-intercalation- photothermal-photodynamic multistage effects

“…These phenomena indicate that TCNCoT has excellent oxidase-like activity only under acidic conditions, which is conducive to targeting the bacterial acidic microenvironment. We chose the condition of pH=6 to compare the oxidase-like activity of different materials because the pH value of the bacterial microenvironment was approximately 6 [26] . The results show that g-C 3 N 4 and TCN did not discolour TMB, while TCNCo and TCNCoT could discolour TMB, indicating that the oxidase-like activity was derived from Co nanoparticles.…”

An Injectable Hydrogel for Enhanced FeGA-Based Chemodynamic Therapy by Increasing Intracellular Acidity

“…This in turn improved oxidative stress in tumors, resulting in a considerable improvement in the treatment effect of simultaneous chemotherapy or radiotherapy. Although a significant anti-tumor efficacy is attained, the Fenton reaction's effect is highly associated with the acidity of the tumor (19). With the decrease of pH, the reaction rate of Fe2+ with H 2 O 2 increases.…”