Oligonucleotide-linked gold nanoparticle aggregates for enhanced sensitivity in lateral flow assays

Abstract

Lateral flow assays (LFAs) as rapid analytical techniques promise to be widely used in point-of-care (POC) diagnostics because of their affordability and simplicity. However, LFAs still suffer from low sensitivity in detection of various biomarkers, e.g., nucleic acids. In this study, we developed a simple and general one-step signal amplification strategy, which employed oligonucleotide-linked gold nanoparticle (AuNP) aggregates to enhance the sensitivity in nucleic acid lateral flow (NALF) assays. Using a nucleic acid sequence of human immunodeficiency virus type 1 (HIV-1) as a model analyte, we observed that the detection limit of the developed NALF assay was 0.1 nM, which was improved by 2.5-fold compared with that of a non-signal amplification approach. The methodology described here could be used to detect a broad range of nucleic acids, and the general signal amplification approach could be potentially adopted in other types of LFAs.

Improved LFIAs for highly sensitive detection of BNP at point-of-care

“…In our previous study, 23 the lateral flow test strip was constituted with NC membrane, absorbent pad and sample pad ( Figure 2A[i]). However, throughout our experiment on BNP detection, we found that the complex of GNP-Ab was unable to completely wick through the previously used sample pad, resulting in the waste and reduction of the effective tracer and degrade the detection sensitivity.…”

“…Therefore, BNP represents a vital blood cardiac biomarker in patients with acute myocardial infarction and advanced HF. 12 With advances in POC testing, [18][19][20][21][22] lateral flow assays (LFAs) hold tremendous potential to address the abovementioned challenges 23,24 due to the simple, affordable and user-friendly features. 25 However, the existing LFAs are associated with the limitation of poor sensitivity.…”

“…25 However, the existing LFAs are associated with the limitation of poor sensitivity. 11,26 Several methods have been developed to enhance the sensitivity of LFAs, such as sample concentration, [27][28][29][30] thermal contrast, 31 fluidic control, [32][33][34] temperature-humidity technique, 35 probe-based signal enhancement, 23,36 enzyme-based signal amplification 37,38 and electrochemical devices-based enhancement. 39 However, these approaches require either external equipment, 35 high-cost reagents 23,37 or complicated fabrication with multistep procedure, 32 limiting their application for POC testing.…”

A Review on Lateral Flow Test Strip for Food Safety

“…To overcome this limitation, researchers have worked on different labeling tags, including silver or gold enhancement (Anfossi et al, 2013;Hu et al, 2013), chemiluminescent tags or fluorescent tags (Zou et al, 2010;Berlina et al, 2013;Bruno, 2014;Taranova et al, 2015), magnetic nanoparticles Wang et al, 2013), and carbon nanoparticles (Noguera et al, 2011). Anfossi et al (2013) amplified the detection signal of an ochratoxin by using a detection LFTS that utilizes silver nucleation on gold nanoparticles.…”

Practical High-Performance Lateral Flow Assay Based on Autonomous Microfluidic Replacement on a Film

“…Among POCT devices, paper-based devices have been seen as the ideal platform for point-of-care (POC) diagnostics due to their very low cost, simplicity, and inherent ability to wick fluids. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] Fluid transport eliminates expensive pumping instrumentation and complicated handling. 16,17 The porous structure of paper is very convenient for dot-immunobinding assays, and cellulose itself has high affinity to biomolecules.…”