A Self-Immolative Fluorescent Probe for Selective Detection of SARS-CoV-2 Main Protease

Abstract

Existing tools to detect and visualize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) suffer from low selectivity, poor cell permeability, and high cytotoxicity. Here we report a novel self-immolative fluorescent probe (MP590) for the highly selective and sensitive detection of the SARS-CoV-2 main protease (M pro ). This fluorescent probe was prepared by connecting a M pro -cleavable peptide ( N -acetyl-Abu-Tle-Leu-Gln) with a fluorophore ( i . e ., resorufin) via a self-immolative aromatic linker. Fluorescent titration results show that MP590 can detect M pro with a limit of detection (LoD) of 35 nM and is selective over interferents such as hemoglobin, bovine serum albumin (BSA), thrombin, amylase, SARS-CoV-2 papain-like protease (PL pro ), and trypsin. The cell imaging data indicate that this probe can report M pro in HEK 293T cells transfected with a M pro expression plasmid as well as in TMPRSS2-VeroE6 cells infected with SARS-CoV-2. Our results suggest that MP590 can both measure and monitor M pro activity and quantitatively evaluate M pro inhibition in infected cells, making it an important tool for diagnostic and therapeutic research on SARS-CoV-2.

Hijacking the self-replicating machine of bacteriophage for PCR-based cascade signal amplification in detecting SARS-CoV-2 viral marker protein in serum

“…Since the outbreak of COVID-19 [1] , many effort has been devoted to developing effective signal amplification methods to improve the sensitivity in detecting SARS-Cov-2 [2] , [3] , [4] , [5] . And many encouraging results have been reported [6] , [7] , [8] , [9] , [10] . One main theme in this field is to use enzymes to guide nucleic acids into cycles and cascades of reactions [11] , [12] , [13] , [14] .…”

A Computational Perspective on the Reactivity of π‐spacers in Self‐Immolative Elimination Reactions

“…While this approach is notably effective for the controlled release of drugs, its applications extend beyond pharmaceuticals into diverse fields, ranging from the design of self‐degrading polymers to the release of probes for sensing [5–10] . For example, in the realm of self‐degrading polymers, [11–14] this strategy enables the decomposition of polymers in response to a specific stimulus, yielding their constituent building blocks.…”

Dual-Parameter Recognition-Directed Design of the Activatable Fluorescence Probe for Precise Imaging of Cellular Senescence

“…Fluorescence imaging, owing to many merits such as high sensitivity, nanometer spatiotemporal resolution, dynamic feedback, and convenience, has become an indispensable technique for real-time analysis and dynamic visualization of important biological events in complex living systems at the cellular and molecular levels. − Indeed, considerable efforts have been devoted to constructing fluorescent probes by virtue of the unique biochemical features during cellular senescence, which are routinely designed by detecting the expression of senescence-associated beta-galactosidase (SA-β-gal), − currently the gold-standard biomarker of senescence. Although tracking senescence has been achieved in several cellular and animal models, the reliability of these probes is often concerned, because the overexpression of SA-β-gal has also been identified in some non-senescent cells. − To overcome this limitation, recent attempts have been made to develop probes by targeting other potential features including lipofuscin, sialidase, α-fucosidase, and ions .…”