Ratiometric fluorescence sensing of copper ion and enzyme activity by nanoprobe-mediated autocatalytic reaction and catalytic cascade reaction

• Published in: Sensors and actuators. B, Chemical Chemical, 2020-05, Vol.310, p.127873-9, Article 127873
• Main Authors: Dong, Ping, Liu, Yahua, Zhao, Yun, Wang, Wenxiao, Pan, Min, Liu, Yu, Liu, Xiaoqing
• Format: Article
• Language: English
• Subjects: Alkaline phosphatase; Amplification; Cascade chemical reactions; Cascade reaction; Catalysis; Detection; Enzyme activity; Enzyme assay; Enzymes; Fluorescence; Fluorescence detection; Nanoprobe; Optical biosensor; Performance enhancement
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2020.127873

The integration of ratiometric technique with catalytic reaction provides a viable approach for amplified and reliable ratiometric fluorescence analysis. [Display omitted] •Ratiometric signal amplification method based on catalytic cascade reactions (integrating the natural biocatalysis with copper ion-mediated autocatalytic reaction of o-phenylenediamine) was proposed for the first time.•The ratiometric analysis with catalytic cascade reactions allows amplified optical sensing of enzymes activity including alkaline phosphatase and acetylcholinesterase and their inhibitors.•This ratiometric optical sensor could provide the information about the enzymatic reaction kinetics of alkaline phosphatase and acetylcholinesterase. Despite the tremendous potential of ratiometric method, its development has been limited by challenges such as the lack of signal amplification. Ratiometric sensing that is highly reliable, sensitive and selective would greatly facilitate optical analysis. Inspired by the natural biocatalysis and cascade catalysis, we demonstrate that the nanoprobe-mediated ratiometric detection coupled with autocatalytic reaction enables fluorescence sensing with ultrahigh sensitivity. Furthermore, the integration of the ratiometric analysis with catalytic cascade reactions allows amplified optical sensing of enzyme activity including alkaline phosphatase or acetylcholinesterase and their inhibitors. Our data show that ratiometric nanoplatforms combined with autocatalytic reaction or catalytic cascade reactions mediated by nanoprobes may represent a viable approach to improve performance of fluorescence sensing.