Published: Oct. 22, 2023

Nanozymes are a new class of nanomaterials that can mimic the activity some natural enzymes. [1] Thanks to their versatility, robustness, low manufacturing costs, and long shelf life, which make them easier handle compared counterparts, nanozymes have been widely applied in clinical diagnostic, wastewater pollutant remediation, proposed as antimicrobial, environmental treatments, anticancer agents, etc. [2] Although effect nanozymes' on substrates is similar enzymes, catalytic mechanisms drastically different, usually suffer for lower specificity activity. [3] These aspects often overlooked literature, point dominated field last decade oxidase- (OX) peroxidase-like (POD) activities, such cerium iron oxide nanoparticles, recently questioned catalysts due very efficiency. [4], [5] Thus, studies aiming clarify real advantages drawbacks respect counterparts strongly demanded field, especially emerging nanomaterials.Recently, possessing multi-enzymatic emerged. [6] Among them, platinum nanoparticles (PtNPs), displaying OX, POD, catalase-like (CAT) gaining momentum, nanomedicine reactive oxygen species scavenging, [7] antioxidant detection, [8] antimicrobial. [9] Nevertheless, there still much disclose concerning PtNPs enzyme-like how these affected by parameters. Most topic based computational calculations, with little, if any, [10] experimental validation, performed alloys rather than pure nanoparticles. [11] The lack in-depth knowledge this regard hinders development PtNP applications current understanding biological behavior.In work, we an systematic study investigating three known oxidoreductase-like activities function different chemical physical parameters, varying pH, temperature, buffer media, substrates. We observed generally more active at acidic increases temperature. Interestingly, CAT-like was found be dependent composition, while dependency less marked OX- POD-like activities. Different colorimetric assays were commonly used test Surprisingly, most easily produce misleading results, instability chromogenic probes conditions, or because solvents, employed solubilize substrates, even commercial kits, interfere Furthermore, sort substrate selectivity nanozyme observed, related affinity surface PtNPs.In second part study, Pt enzymes: mammal catalase activity, fungal laccase OX-like horseradish peroxidase (HRP) To compare its calculated turnover frequency (TOF) same while, recyclability catalysts, number (TON). Despite differences mechanisms, comparable one enzymes higher harsh where, contrary, become inactive.In investigated underlying properties. Utilizing detection reagents high specific radicals, determined hydroxyl radical main player CAT- dissolved concentration. actually deeply interconnected and, although they occur simultaneously, favored over others tuning relative concentration catalyst.In summary, present provides comprehensive characterization multi-enzyme important insights pivotal interest implementation Pt-based sensing applications.

Language: Английский