A new post-synthesis strategy is developed to achieve reversible regulation of nanozyme's activity.
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Fe3+-mediated aggregation can enhance the peroxidase-like activity of MoS2 quantum dots more than 10 times.
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Quality control of captopril in pharmaceutical products is realized by manipulating nanozyme's catalytical activity.
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This sensing approach allows smartphone read-out, which has promising applications in point-of-care testing.
Abstract
Regulating the catalytic activity of nanozymes is significant for their applications in various fields. Here, we demonstrate a new strategy to achieve reversible regulation of the nanozyme's activity for sensing purpose. This strategy involves the use of zero-dimensional MoS2 quantum dots (MQDs) as the building blocks of nanozymes which display very weak peroxidase (POD)-like activity. Interestingly, such POD-like activity of the MQDs largely enhances in the presence of Fe3+ while diminishes with the addition of captopril thereafter. Further investigations identify the mechanism of Fe3+-mediated aggregation-induced enhancement of the POD-like activity and the inhibitory effect of captopril on the enhancement, which is highly dependent on their concentrations. Based on this finding, a colorimetric method for the detection of captopril is developed. This sensing approach exhibits the merits of simplicity, rapidness, reliability, and low cost, which has been successfully applied in quality control of captopril in pharmaceutical products. Moreover, the present sensing platform allows smartphone read-out, which has promising applications in point-of-care testing devices for clinical diagnosis and drug analysis.
