Analytical Sciences
Online ISSN : 1348-2246
Print ISSN : 0910-6340
ISSN-L : 0910-6340
Original Papers
Highly Sensitive Fluorescent Immunoassay of Human Immunoglobulin G Based on PbS Nanoparticles and DNAzyme
Zhen-Zhen HUANG FULi-Juan HAOYan-Mei WUHai-Ying QIAOZi YIXiao-Yan LIXia CHU
Author information

2013 Volume 29 Issue 5 Pages 499-504


This paper reports a highly sensitive fluorescent immunoassay for the detection of human immunoglobulin G based on PbS nanoparticles and DNAzyme. A sandwich immunoassay format was performed on a microtiter plate. Goat anti-human IgG was coated onto the polystyrene microtiter plate. The human IgG analyte was first captured by the goat anti-human IgG, and then sandwiched by a goat anti-human IgG antibody labeled with PbS nanoparticles. After being dissolved with HNO3, the released Pb2+ made the substrate chain of the DNAzyme labeled with the fluorophore dissociate from the enzyme strand of the DNAzyme labeled with the quencher, which resulted in fluorescence recovery. Then, the human IgG could be detected indirectly from the fluorescent signals. Under the optimized conditions, the linear range of the developed immunosensor was from 1 ng mL−1 to 10 μg mL−1 with a detection limit of 0.8 ng mL−1. This immunosensor could be used to detect the amount of human IgG in human serum samples.

Information related to the author
© 2013 by The Japan Society for Analytical Chemistry
Previous article Next article