In situ formation of copper nanoclusters for efficient analysis of β-glucosidase activity

Abstract

An efficient and convenient fluorescent method has been developed to detect β-glucosidase via utilizing the in situ synthesis of double-stranded DNA templated copper nanoclusters (dsDNA-Cu NCs). The dsDNA-Cu NCs can be formed by using random dsDNA with (AT-TA) rich sequence as the template. However, with the addition of amygdalin and β-glucosidase, amygdalin was catalyzed by β-glucosidase to generate cyanide ion (CN−). The CN− had the high affinity to bind with Cu2+ to inhibit the production of fluorescent dsDNA-Cu NCs, resulting in low fluorescence intensity. This method exhibits both sensitivity and specificity in detecting β-glucosidase under the optimal conditions. In addition, the technique's detection limit is 0.00084 U mL−1. The serum samples were also used to verify this fluorescent strategy with satisfactory results. In addition, this method does not require complex preparation process of probes and fluorescent dye labelling, greatly simplifying the experimental processes. Thus, it can provide a sensitive method for the β-glucosidase related biomedical research.