Engineering Inorganic Nanoflares with Elaborate Enzymatic Specificity and Efficiency for Versatile Biofilm Eradication

Abstract

nanozyme-catalyzed reactive oxygen species (ROS) generation has recently been used for detecting ROS and the as-related biomolecules. [5] ROS are oxygen-relevant reactive species, including superoxide (•O 2 −), hydrogen peroxide (H 2 O 2), and hydroxyl radical (•OH), are endogenously generated through aerobic metabolism. [6] Notably, oxidative stress emerged once the upregulated ROS overwhelmed the cellular antioxidant response, and was associated with carcinogenesis and neurodegeneration. [7] Accordingly, the antioxidants are supplemented as "free-radical scavengers" for eliminating the overexpressed ROS. [8] The antioxidants deficiency increases the susceptibility to cardiovascular diseases and skin infections. [9] Thereby, the efficient nanozyme-mediated accurate quantification of ROS and antioxidants is highly desirable. Various nanozymes have been adapted as potential candidates for detecting ROS and antioxidants. [10] Platinum nanoparticles (PtNPs) represents the superior nanozyme yet its low economy and specificity remained as the major challenges for their extensive applications. More efforts have currently been payed to the construction of specific nanozyme catalysts via surface modifications. For example, the substrate-specific Fe 3 O 4 nanozyme has been constructed by integrating with molecularly imprinted polymers with specific substrate-recognitions. [11] Meanwhile, the activity of Pt-based nanozyme could be improved by introducing a surface modifier β-casein that could recognize a specific substrate via electrostatic, hydrophobic and hydrophilic interactions. [12] Therefore, an appropriate surface modification could supplement the straightforward route to improve the catalytic capabilities and specificities of Pt-based nanozyme. [13] Accordingly, the PtNPs could be modified with substrate recognition nanomaterials for constructing the highly specific and efficient nanozyme. Attractively, the high quantum yield and photostability of carbon dots (CDs) have enabled CDs to be excellent fluorescent probes yet their nanoenzymatic properties are always ignored originating from their low catalytic efficiency. It is demonstrated that the combination of metal and carbon can introduce higher catalytic activity in comparison to the individual metal and carbon nanomaterials, originating from their efficient interfacial electron transfer. [14] Besides, the fluorescent CDs could also be served as the docking sites for specific substrates via electrostatic and Nanozyme has emerged as a versatile nanocatalyst yet is constrained with limited catalytic efficiency and specificity for various biomedical applications. Herein, by elaborately integrating the recognition/transduction carbon dots (CDs) with platinum nanoparticles (PtNPs), an exquisite CDs@PtNPs (CPP) nanoflare is engineered as an efficient and substrate-specific peroxidasemimicking nanozyme for high-performance biosensing and antibacterial applications. The intelligent CPP-catalyzed hydrogen peroxide (H 2 O 2)-generated reactive oxygen species realize the se...

Peroxidase‐Mimetic Copper‐Doped Carbon‐Dots for Oxidative Stress‐Mediated Broad‐Spectrum and Efficient Antibacterial Activity

“…As shown therein, Cu‐CDs presented a competitive antibacterial performance and an excellent biocompatibility (see infra) as well. In several other mimic peroxidase‐based antimicrobial agents, additional H 2 O 2 is essential for the generation of a high yield of ⋅OH [6,10,52,53] . It is worth mentioning that endogenous H 2 O 2 was dominant in this Cu‐CD‐induced antibiosis system.…”

“…In several other mimic peroxidase-based antimicrobial agents, additional H 2 O 2 is essential for the generation of a high yield of * OH. [6,10,52,53] It is worth mentioning that endogenous H 2 O 2 was dominant in this Cu-CD-induced antibiosis system. Most of the previously reported antimicrobic CDs required activation with visible/natural light.…”

Ultrasmall copper nanoclusters with multi-enzyme activities

“…where V max is the maximum reaction rate; [E] is the concentration of enzymes or CuNCs. 40,41 The V max were obtained from Lineweaver-Burk plot and calculated to be 8.8 Â 10 À8 M s À1 and 5.15 Â 10 À8 M s À1 for H 2 O 2 and TMB substrates. From Table S1, † we can nd that V max of CuNCs was even higher than HRP.…”

Triple-synergistic MOF-nanozyme for efficient antibacterial treatment

“…Among them, ROS has been proved to be a rapid, effective, and broad-spectrum antibacterial and even anti-cancer strategy, and it is not inclined to promote drug-resistant bacteria [ [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] ]. Moreover, ROS is reactive with DNA and lipids of inactive bacteria, especially to the multidrug-resistant “superbugs” and the refractory biofilms, exhibiting an excellent antibacterial potential [ 32 ]. However, the direct introduction of high concentrated H 2 O 2 will cause damage to normal tissues [ 33 ].…”