Preparation of visible-light-excited luminescence enhancement solutions for time-resolved luminescence detection of europium biolabel.
Dissociation enhanced lanthanide fluoroimmunoassay (DELFIA) technique based on EDTA-Eu(3+) derivative biolabels is the most widely used time-resolved luminescence bioassay technique for clinical diagnosis, but its major drawback is that the conventional luminescence enhancement solution of EDTA-Eu(3+) requires UV excitation (<360 nm). In this work, three new visible-light-excited luminescence enhancement solutions are developed and their luminescence response behaviors to EDTA-Eu(3+) are systematically investigated. The new solutions were prepared by co-dissolving a newly synthesized tetradentate β-diketone, 1,2-bis[8'-(1'',1'',1'',2'',2'',3'',3''-heptafluoro-4'',6''-hexanedion-6''-yl)-naphth-2'-yl]-benzene (BHHNB), and one of three derivatives of triazine, 2-(N,N-diethylanilin-4-yl)-4,6-bis(3,5-dimethylpyrazol-1-yl)-1,3,5-triazine (DPBT), 2-(N,N-diethylanilin-4-yl)-4,6-bis(3-methylpyrazol-1-yl)-1,3,5-triazine (MPBT) or 2-(N,N-diethylanilin-4-yl)-4,6-bis(pyrazol-1-yl)-1,3,5-triazine (BPT), in a weakly acidic aqueous buffer at pH 3.2 containing 0.1% Triton X-100. These solutions showed sensitive and rapid luminescence responses to non-luminescent EDTA-Eu(3+) by the formation of the ternary Eu(3+) complexes, BHHNB-Eu(3+)-DPBT, BHHNB-Eu(3+)-MPBT and BHHNB-Eu(3+)-BPT. These complexes have long luminescence lifetimes (>500 μs) and a wide excitation wavelength range from UV to visible light with the excitation peaks at 390, 400 and 420 nm, respectively, which enabled the solutions to be used as visible-light-excited luminescence enhancement solutions for the highly sensitive time-resolved luminescence detection of EDTA-Eu(3+).
State Key Laboratory of Fine Chemicals, School of Chemistry, Dalian University of Technology, Dalian 116024, China.
Hui
H
Zhang
Lu
L
Tian
Ruoyu
R
Zhang
Zhiqiang
Z
Ye
Jingli
J
Yuan
D056831:Coordination Complexes / Q000737:chemistry; D004492:Edetic Acid / Q000737:chemistry; D005063:Europium / Q000032:analysis*; D015200:Fluoroimmunoassay; D006863:Hydrogen-Ion Concentration; D008027:Light; D008163:Luminescent Measurements; D012996:Solutions / Q000737:chemistry; D013997:Time Factors; D014227:Triazines / Q000737:chemistry
D056831:Coordination Complexes; D012996:Solutions; D014227:Triazines; D005063:Europium; D004492:Edetic Acid