A novel enhancement assay for immunochromatographic test strips using gold nanoparticles |
| |
Authors: | Ryo Tanaka Teruko Yuhi Naoki Nagatani Tatsuro Endo Kagan Kerman Yuzuru Takamura Eiichi Tamiya |
| |
Institution: | (1) School of Materials Science, Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Nomi Ishikawa, 923-1292, Japan;(2) Japan Science and Technology Agency (JST), Innovation Plaza Ishikawa, 2-13 Asahidai, Nomi Ishikawa, 923-1211, Japan;(3) Department of Biotechnology and Applied Chemistry, Faculty of Engineering, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan;(4) Department of Mechano-Micro Engineering, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku Yokohama, 226-8502, Japan |
| |
Abstract: | The immunochromatographic assay is a well-known and convenient diagnostic system. In this report, the development of a novel
enhancement assay for the test strips is described. Additionally, this highly sensitive immunochromatographic assay was applied
to detect human chorionic gonadotropin hormone (HCG) as the model case. The primary antibody-conjugated gold nanoparticles
were used as the enhancer of the standard method. The primary antibodies were immobilized within a defined detection zone
(test line) on the diagnostic nitrocellulose membrane. The secondary antibodies were conjugated with colloidal gold nanoparticles.
In combination with an effective sample pretreatment, the gold-conjugated antibodies and the primary antibodies formed a sandwich
complex with the target protein. Within the test line, the sandwich complex was immobilized, and furthermore, concentrated
by the enhancer resulting in a localized surface plasmon resonance (LSPR) phenomenon and a distinct red color on the test
line. The intensity of color of the red test line (signal intensity), which correlated directly with the concentration of
the target protein in the standard or spiked samples, was assessed visually and by computer image analysis using a three-determination
analysis. Under optimum conditions, the limit of detection (LOD) for HCG assay was 1 pg/mL. When using human serum, 10 pg/mL
of HCG could be detected. We have also spiked total prostate-specific antigen (TPSA) in female serum. The LOD for TPSA was
determined as 0.2 ng/mL. With this method, the quantitative determination of the target protein could be completed in less
than 15 min. Our novel immunochromatographic strips using the enhancing method based on LSPR of gold nanoparticles are useful
as a rapid and simple screening method for the detection of important analytes for medical applications, environmental monitoring,
food control, and biosecurity.
![MediaObjects/216_2006_549_Figa_HTML.jpg](/content/y4173714713h0h85/MediaObjects/216_2006_549_Figa_HTML.jpg) |
| |
Keywords: | Gold immunochromatographic assay Colloidal gold nanoparticles Human chorionic gonadotropin hormone Total prostate-specific antigen |
本文献已被 PubMed SpringerLink 等数据库收录! |
|