Akademik Veri Yönetim Sistemi
MICROCHIMICA ACTA, cilt.182, sa.7-8, ss.1457-1464, 2015 (SCI-Expanded)
A highly sensitive amperometric magnetoimmunoassay for rapid determination of lipoprotein(a) (Lp(a)), an important predictor of cardiovascular disease risk, in human serum, is described. It uses a sandwich configuration involving selective capture antibody [antiLp(a)] and biotinylated detector antibody [biotin-antiLp(a)], and a streptavidin-HRP conjugate on carboxy-modified magnetic beads (HOOC-MBs). The resulting MBs bearing the sandwiched immunoconjugates were captured by a magnet placed under the working electrode surface of a disposable screen-printed carbon electrode and the extent of the affinity reaction was monitored amperometrically at -0.20 V (vs a silver pseudo-reference electrode) in the presence of hydroquinone as an electron transfer mediator and upon addition of H2O2 as the enzyme substrate. The method exhibited a wide linear response range (from 0.01 to 0.5 mu g mL(-1)), a detection limit of 4 ng mL(-1), and an excellent selectivity over other serum components. The utility of the immunoassay was demonstrated by analyzing a reference serum containing a certified quantity of Lp(a). The performance of this magnetoimmunoassay compares favorably to that of an integrated amperometric immunoassay described earlier.