An electrochemiluminescence flow-through cell and its applications to sensitive immunoassay using N-(aminobutyl)-N-ethylisoluminol.
An electrochemiluminescence (ECL) flow-through cell with a carbon fiber electrode for ECL detection was developed, and a flow injection analysis system containing the cell was established. N-(aminobutyl)-N-ethylisoluminol (ABEI), an ECL reagent, was determined by this system. A straight-line calibration curve for ABEI (r = 0.999) was obtained from 6 fmol to 25 pmol. The detection limit of ABEI was 6 fmol (S/N = 2) and the relative standard deviation was 1.7% at 1.5 pmol (n = 10). The system was used for immunoassay of human immunogloblin G (hIgG) with ABEI-labeled anti-hIgG. A calibration curve of hIgG was obtained from 80 pg/mL to 1.3 ng/mL. The detection limit of hIgG was 80 pg/mL (S/N = 2), and the relative standard deviation was 1.8% at 0.5 ng/mL (n = 10). Sensitivity and accuracy for sera samples were found to considerably exceed those of the conventional methods, such as single-radial immunodiffusion and nepherometric immunoassay. The present system should prove useful for immunoassay.
Arai
K
K
School of Pharmacy, Tokyo University of Pharmacy and Life Science, Japan.
Takahashi
K
K
Kusu
F
F
D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods*; D004566:Electrodes; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007074:Immunoglobulin G / Q000032:analysis; D008163:Luminescent Measurements; D008165:Luminol / Q000031:analogs & derivatives* / Q000737:chemistry
D007074:Immunoglobulin G; D008165:Luminol