Biosensors and Bioelectronics, 2015, 01, 69─73

Highly sensitivedetectionof a bio-threat pathogenby goldnanoparticle-based oligonucleotide-linked immunosorbentassay

Sang-Hwan Seo, Young-Ran Lee, Jun Ho JeonYi-Rang Hwang, Pil-Gu Park, Dae-Ro Ahn, Ki-Cheol Han, Gi-Eun Rhie, Kee-Jong Hong

Abstract

Francisella (F.) tularensis causes the zoonotic disease tularemia and categorized as one of the highest-priority biological agents. The sensing approaches utilized by conventional detection methods, including enzyme-linked immunosorbent assay (ELISA), are not sensitive enough to identify an infectious dose of this high-risk pathogen due to its low infective dose. As an attempt to detect F. tularensis with high sensitivity, we utilized the highly sensitive immunoassay system named gold nanoparticle-based oligonucleotide-linked immunosorbent assay (GNP-OLISA) which uses antibody-gold nanoparticles conjugated with DNA strands as a signal generator and RNA oligonucleotides appended with a fluorophore as a quencher for signal amplification. We modified the GNP-OLISA for the detection F. tularensis to utilize one antibody for both the capture of the target and for signal generation instead of using two different antibodies, which are usually employed to construct the antibody sandwich in the ELISA. The GNP-OLISA showed 37-fold higher sensitivity compared with ELISA and generated very consistent detection results in the sera. In addition, the detection specificity was not affected by the presence of non-target bacteria, suggesting that GNP-OLISA can be used as a sensitive detection platform for monitoring high-risk pathogens thereby overcoming the limit of the conventional assay system.

• ISBN or ISSN: 0956-5663

• 본 연구는 질병관리본부 연구개발과제(과제번호 2013-NG45003-00) 연구비를 지원받아 수행되었습니다.
• This research was supported by a fund(code 2013-NG45003-00) by Research of Korea Centers for Disease Control and Prevention.