2D-Metal–Organic-Framework-Nanozyme Sensor Arrays for Probing Phosphates and Their Enzymatic Hydrolysis

Abstract

The detection of phosphates and their enzymatic hydrolysis is of great importance because of their essential roles in various biological processes and numerous diseases. Compared with individual sensors for detecting one given phosphate at a time, sensor arrays are able to discriminate multiple phosphates simultaneously. Although nanomaterial-based sensor arrays have shown great promise for the discrimination of phosphates, very few of them have been explored for probing phosphates involved enzymatic hydrolysis. To fill this gap, herein we fabricated two-dimensional-metal-organic-framework (2D-MOF)-nanozyme-based sensor arrays by modulating their peroxidase-mimicking activity with various phosphates, including AMP, ADP, ATP, pyrophosphate (PPi), and phosphate (Pi). The sensor arrays were used to successfully discriminate the five phosphates not only in aqueous solutions but also in biological samples. The practical application of the sensor arrays was then validated with blind samples, where 30 unknown samples containing phosphates were accurately identified. Moreover, the sensor arrays were successfully applied to probing hydrolytic processes involving ATP and PPi that are catalyzed by apyrase and PPase, respectively. This work demonstrates a nanozyme-based sensor array as a convenient and reliable analytical platform for probing phosphates and their related enzymatic processes, which could be applied to other analytes and enzymatic reactions.

Self‐limited Phosphatase‐mimicking CeO2 Nanozymes

“…The product gluconic acid can inhibit the reaction, which could be due to the stronger affinity of the acid or the released proton to lower the pH . While the effects of phosphate and polyphosphate on oxidase and peroxidase mimicking nanozymes have been studied, this is the first report on phosphatase nanozymes.…”

Antioxidant Materials Based on 2D Nanostructures: A Review on Recent Progresses

“…While the bare MOF was attested to be a peroxidase mimic (in acidic buffers near pH 3-4, similar for all MOFs with peroxidase activity), Au deposition turned the material into a GOx mimic, after which the concentration of gluconic acid was measured by a photometric assay. Similarly, Qin et al used the same Fe-TCPP in Zn, Co and Cu-MOFs as peroxidases with altered activity in the presence of numerous phosphates of biological relevance [152]. Based on their activity change, the peroxidase probe reaction was utilized to detect the biomolecules mixed with the MOFs.…”

Nanozyme‐based luminescence detection

“…To date, nanozymes have been reported to mimic oxidase, peroxidase, catalase, superoxide dismutase, alkaline phosphatase, and nuclease. [ 4–8 ] Nanozymes have been widely used for analytical applications [ 9–15 ] such as replacing horseradish peroxidase (HRP) for signal amplification in immunoassays. In addition, some molecules can regulate the activity of nanozymes and therefore are classified as promotors or inhibitors.…”