A highly sensitive luminescent probe based on Ru(II)-bipyridine complex for Cu2+, L-Histidine detection and cellular imaging

摘要

A ruthenium(II) bipyridyl complex conjugated with functionalized Schiff base (RuA) has been synthesized and functioned as a luminescent probe. The luminescence of RuA was greatly quenched by Cu2+ due to its molecular coordination with paramagnetic Cu2+. Subsequently, the addition of L-Histidine can turn on the luminescence of the RuA-Cu(II) ensemble, which can be attributed to the replacement of RuA in RuA-Cu(II) ensemble by L-Histidine. On the basis of the quenching and recovery of the luminescence of RuA, we proposed a rapid and highly sensitive on-off-on luminescent assay for sensing Cu2+ and L-Histidine in aqueous solution. Under the optimal conditions, Cu2+ and L-Histidine can be detected in the concentration range of 5 nM-9.0 mu M and 50 nM-30 mu M, respectively, and the corresponding detection limits were calculated to be 035 and 0.44 nM (S/N=3), separately. The proposed luminescent probe has been successfully utilized for the analysis of Cu2+ and L-Histidine in real samples (drinking water and biological fluids). Furthermore, the probe revealed good photostability, low cytotoxicity and excellent permeability, making it a suitable candidate for cell imaging and labeling in vitro. (C) 2018 Elsevier B.V. All rights reserved.