Open AccessA Cu II ‐Salicylidene Glycinato Complex for the Selective Fluorometric Detection of Homocysteine over 20 Proteinogenic Amino Acids
Author(s) -
Li Xuecong,
Yadav Prerna,
Spingler Bernhard,
Zelder Felix
Publication year - 2022
Publication title -
chemistryopen
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 29
ISSN - 2191-1363
DOI - 10.1002/open.202200106
Subject(s) - fluorescence , cysteine , chemistry , amino acid , homocysteine , histidine , analyte , selectivity , glycine , biochemistry , stereochemistry , combinatorial chemistry , chromatography , enzyme , physics , quantum mechanics , catalysis
Homocysteine (Hcy) is a sulfur‐containing α‐amino acid that differs by one methylene (CH 2 ) subunit from homologous cysteine (Cys). Elevated levels of Hcy are diagnostic markers of cardiovascular disease and other medical conditions. We present a new Cu II ‐salicylidene glycinato complex 1 for the selective fluorometric detection of Hcy in water. In the presence of this analyte, the non‐fluorescent copper‐complex demetallates and disassembles into its building blocks. This process liberates a 3‐chloro‐5‐sulfosalicylaldehyde signaling unit and is accompanied by a 51‐fold turn‐on fluorescence at 485 nm (λ ex =350 nm). Out of twenty proteinogenic amino acids, only histidine (12‐fold turn‐on fluorescence) and Cys (8‐fold turn‐on fluorescence) trigger some disassembly of probe 1 . In comparison with important pioneering work on the detection of biothiols, this study strikingly demonstrates that structural modifications of chelate core structures steer substrate selectivity of metal‐based probes. Importantly, probe 1 has proven suitable for the detection of Hcy in artificial urine.