Macromolecules-triggered, light-activated oxidase mimic for versatile colorimetric biosensors with signal-switching functionality

Colorimetric biosensors are suitable for point-of-care assays due to the advantages of simple operation, fast analysis and direct visualization. Here a novel oxidase mimic of thioflavin T via light-activating was first discovered. Various chromogenic substrates can be efficiently oxidized via light-activated singlet oxygen ( 1 O 2 ). In particular, thioflavin T often binds to some unique conformations in bio-macromolecules (e.g., DNA G-quadruplex) with good specificity. This is valuable to develop versatile colorimetric biosensors with signal-switching functionality for direct visualizing of analytes. Using various recognition elements (molecular beacons, aptamers), we can realize the efficient assay of five different analytes, including mechlorethamine , DNA, K + , adenosine monophosphate, and amyloid fibril . Therefore light-activated oxidase mimic of thioflavin T can serve as a desirable tool to assay various analytes of pharmaceutical, food or environmental interest.