Black phosphorus nanosheets based sensitive protease detection and inhibitor screening

Proteases, as one of the most significant kind of digestive enzymes, are closely related to a variety of physiological processes and diseases. Herein, a black phosphorus nanosheets (BPs) based sensitive fluorometric method for protease detection and inhibitor screening is proposed. The aqueous solution of perylene probe (probe 1) displays a strong fluorescence. BPs, as novel discovered two-dimensional (2D) materials, can adsorb probe 1 through electrostatic interactions, which causes fluorescence quenching of probe 1. Histone can control the interactions between the perylene probe and BPs, which can be further regulated by the introduction of a protease. Thus, the protease activity can be monitored by detecting the fluorescence intensity changes of probe 1. The method is label free, sensitive and selective. As low as 1 ng/mL trypsin can be easily detected. [Display omitted] •Black phosphorus nanosheets were used as the quencher for a fluorometric assay.•A label-free method for protease detection and inhibitor screening.•Histone controlled interactions between a perylene probe and black phosphorus nanosheets were used for signal transduction.•No covalent modifications were needed, and the assay is simple, sensitive and selective.