Affiliations 

  • 1 The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China
  • 2 Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China
  • 3 Xi'an Diandi Biotech Company , Xi'an, Shaanxi 710049, PR China
  • 4 School of Life Sciences, Northwestern Polytechnical University , Xi'an, Shaanxi 710072, PR China
  • 5 Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education, School of Energy and Power Engineering, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China
  • 6 Department of Biomedical Engineering, Faculty of Engineering, University of Malaya , Lembah Pantai, 50603 Kuala Lumpur, Malaysia
Anal. Chem., 2016 06 21;88(12):6254-64.
PMID: 27012657 DOI: 10.1021/acs.analchem.6b00195

Abstract

In nucleic acid testing (NAT), gold nanoparticle (AuNP)-based lateral flow assays (LFAs) have received significant attention due to their cost-effectiveness, rapidity, and the ability to produce a simple colorimetric readout. However, the poor sensitivity of AuNP-based LFAs limits its widespread applications. Even though various efforts have been made to improve the assay sensitivity, most methods are inappropriate for integration into LFA for sample-to-answer NAT at the point-of-care (POC), usually due to the complicated fabrication processes or incompatible chemicals used. To address this, we propose a novel strategy of integrating a simple fluidic control strategy into LFA. The strategy involves incorporating a piece of paper-based shunt and a polydimethylsiloxane (PDMS) barrier to the strip to achieve optimum fluidic delays for LFA signal enhancement, resulting in 10-fold signal enhancement over unmodified LFA. The phenomena of fluidic delay were also evaluated by mathematical simulation, through which we found the movement of fluid throughout the shunt and the tortuosity effects in the presence of PDMS barrier, which significantly affect the detection sensitivity. To demonstrate the potential of integrating this strategy into a LFA with sample-in-answer-out capability, we further applied this strategy into our prototype sample-to-answer LFA to sensitively detect the Hepatitis B virus (HBV) in clinical blood samples. The proposed strategy offers great potential for highly sensitive detection of various targets for wide application in the near future.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.