Chemiluminescent immunoassay of thyroxine enhanced by microchip electrophoresis.
A homogeneous chemiluminescent immunoassay of thyroxine (T4) enhanced by microchip electrophoresis separation has been developed. The method deployed the competitive immunoreaction of T4 and horseradish peroxidase (HRP)-labeled T4 (HRP-T4) with anti-T4 mouse monoclonal antibody (Ab). HRP-T4 and the HRP-T4-Ab complex were separated and quantified by using microchip electrophoresis (MCE) with chemiluminescence (CL) detection. Highly sensitive CL detection was achieved by means of HPR-catalyzed luminol-H(2)O(2) reaction. Due to the effective MCE separation, the CL analytical signal was less prone to sample matrix interference. Under the selected assay conditions, the MCE separation was accomplished within 60s. The linear range for T4 was 5-250 nM with a detection limit of 2.2 nM (signal/noise ratio=3). The current method was successfully applied for the quantification of T4 in human serum samples. It was demonstrated that the current MCE-CL-enhanced competitive immunoassay was quick, sensitive, and highly selective. It may serve as a tool for clinical analysis of T4 to assist in the diagnosis of thyroid gland functions.
Huang
Yong
Y
Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education), College of Chemistry and Chemical Engineering, Guangxi Normal University, Guilin 541004, China.
Zhao
Shulin
S
Shi
Ming
M
Liu
Yi-Ming
YM
D000818:Animals; D055910:Antibodies, Immobilized / Q000276:immunology / Q000378:metabolism; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000378:metabolism; D046209:Electrophoresis, Microchip / Q000379:methods*; D006735:Horseradish Peroxidase / Q000378:metabolism; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008163:Luminescent Measurements; D051379:Mice; D013960:Thyroid Function Tests; D013974:Thyroxine / Q000097:blood*
D055910:Antibodies, Immobilized; D000911:Antibodies, Monoclonal; D006735:Horseradish Peroxidase; D013974:Thyroxine