Development of a Highly Specific, Selective, and Sensitive Fluorescent Probe for Detection of Mycobacteria in Human Tissues

Tuberculosis (TB), including extrapulmonary TB, is responsible for more than one million deaths in a year worldwide. Existing methods of mycobacteria detection have poor sensitivity, selectivity, and specificity, especially in human tissues. Herein, we present the synthesis of a cholic acid-derived fluorescent probe (P4) that can specifically bind and stain the mycobacterium species. We show that P4 probe specifically binds with mycobacterial lipids, trehalose monomycolate, and phosphatidylinositol mannoside 6. P4 probe detects mycobacteria in polymicrobial planktonic cultures and biofilms with high specificity, selectivity, and sensitivity. Moreover, it can detect a single mycobacterium in the presence of 10000 other bacilli. Unlike the probes that depend on active mycobacterial enzymes, the membrane-specific P4 probe can detect mycobacteria even in formalin-fixed paraffin-embedded (FFPE) mice and human tissue sections. Therefore, the ability of the P4 probe to detect mycobacteria in different biological milieu makes it a potential candidate for diagnostic and prognostic applications in clinical settings. This article is protected by copyright. All rights reserved