A long-wavelength fluorescent probe for amino compounds and its application in the determination of aliphatic amines

Abstract

Herein, a highly reactive long-wavelength fluorescent labeling reagent, 1,7-dimethyl-3,5-distyryl-8-phenyl-(4-oxy-acetic acid N-hydroxysuccinimidyl ester) difluoroboradiaza-s-indacene (DMDSPAB-OSu), was designed and synthesized for amino compounds. Using DMDSPAB-OSu as a pre-column derivatization reagent, an HPLC-fluorescence detection method was developed for the determination of trace amounts of aliphatic amines in samples. Prior to analysis, amines were derivatized with DMDSPAB-OSu at room temperature in 0.2 mol L⁻¹ pH 8.8 borate buffer for only 5 min, and the baseline separation of 11 aliphatic amines was achieved within 25 min. Limits of detection between 0.8 to 1.2 nM were obtained at 630 nm with an excitation wavelength of 610 nm. Furthermore, the proposed DMDSPAB-OSu-based HPLC method was applied to the analysis of lake water and human urine with satisfying recoveries ranging from 93.0–109.7%.