A selective and sensitive azido near-infrared fluorescent probe for tris(2-carboxyethyl)phosphine quantitative detection and its application for <i>E. coli</i> determination

摘要： We developed a sensitive near-infrared fluorescent probe, azido hemicyanine (HC-N3), for the detection of tris(2-carboxyethyl)phosphine (TCEP) with the lowest LOD (92 nM) so far. HC-N3 has good selectivity for TCEP among thiols and 20 kinds of natural amino acid. The quantification of E. coli (101–103 cfu mL?1) demonstrated its practicability in complicated biosystems.