Comparative Study of Four Coloured Nanoparticle Labels in Lateral Flow Immunoassay

The detection limit of lateral flow immunoassay (LFIA) is largely determined by the properties of the label used. We compared four nanoparticle labels differing in their chemical composition and colour: (1) gold nanoparticles (Au NPs), red; (2) Au-core/Pt-shell nanoparticles (Au@Pt NPs), black; (3) latex nanoparticles (LPs), green; and (4) magnetic nanoparticles (MPs), brown. The comparison was carried out using one target analyte—Erwinia amylovora, the causal bacterial agent of fire blight. All nanoparticles were conjugated with antibodies through methods that provide maximum functional coverage like physical adsorption (Au NPs, Au@Pt NPs) and covalent bonding (LPs, MPs). All conjugates demonstrated the same ability to bind with E. amylovora through enzyme-linked immunosorbent assay where optical properties of the nanoparticles do not determine the registered signal. However, half-maximal binding was achieved at different numbers of nanoparticles because they differ in size. All conjugates based on four nanoparticle labels were used for lateral flow assays. As a result, Au@Pt NPs provided the minimal detection limit that corresponded to 103 CFU/mL. Au NPs and LPs detected 104 CFU/mL, and MPs detected 105 CFU/mL. The results highlight that simply choosing a coloured label can significantly affect the detection limit of LFIA.

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How to Improve Sensitivity of Sandwich Lateral Flow Immunoassay for Corpuscular Antigens on the Example of Potato Virus Y?

Sensors ◽

10.3390/s18113975 ◽

2018 ◽

Vol 18 (11) ◽

pp. 3975 ◽

Cited By ~ 6

Author(s):

Shyatesa Razo ◽

Vasily Panferov ◽

Irina Safenkova ◽

Yuri Varitsev ◽

Anatoly Zherdev ◽

...

Keyword(s):

Detection Limit ◽

Potato Virus ◽

Potato Virus Y ◽

Polyclonal Antibodies ◽

Test Strip ◽

Lateral Flow ◽

Lateral Flow Immunoassay ◽

Enzyme Linked Immunosorbent Assay ◽

Quantitative Results ◽

Solanaceae Family

A simple approach was proposed to decrease the detection limit of sandwich lateral flow immunoassay (LFIA) by changing the conditions for binding between a polyvalent antigen and a conjugate of gold nanoparticles (GNPs) with antibodies. In this study, the potato virus Y (PVY) was used as the polyvalent antigen, which affects economically important plants in the Solanaceae family. The obtained polyclonal antibodies that are specific to PVY were characterized using a sandwich enzyme-linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR). For LFIA, the antibodies were conjugated with GNPs with a diameter of 17.4 ± 1.0 nm. We conducted LFIAs using GNP conjugates in a dried state on the test strip and after pre-incubation with a sample. Pre-incubating the GNP conjugates and sample for 30 s was found to decrease the detection limit by 60-fold from 330 ng∙mL−1 to 5.4 ng∙mL−1 in comparison with conventional LFIA. The developed method was successfully tested for its ability to detect PVY in infected and uninfected potato leaves. The quantitative results of the proposed LFIA with pre-incubation were confirmed by ELISA, and resulted in a correlation coefficient of 0.891. The proposed approach is rapid, simple, and preserves the main advantages of LFIA as a non-laboratory diagnostic method.

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Comparative Analysis of the Euroimmun CXCL13 Enzyme-Linked Immunosorbent Assay and the ReaScan Lateral Flow Immunoassay for Diagnosis of Lyme Neuroborreliosis

Journal of Clinical Microbiology ◽

10.1128/jcm.00207-20 ◽

2020 ◽

Vol 58 (9) ◽

Author(s):

Katharina Ziegler ◽

Anca Rath ◽

Christoph Schoerner ◽

Renate Meyer ◽

Thomas Bertsch ◽

...

Keyword(s):

Immunosorbent Assay ◽

Roc Curve ◽

Point Of Care ◽

Lateral Flow ◽

Lyme Neuroborreliosis ◽

Diagnostic Tools ◽

Lateral Flow Immunoassay ◽

Enzyme Linked Immunosorbent Assay ◽

European Federation ◽

Point Of Care Test

ABSTRACT Diagnosis of Lyme neuroborreliosis (LNB) is challenging, as long as Borrelia-specific intrathecal antibodies are not yet detectable. The chemokine CXCL13 is elevated in the cerebrospinal fluid (CSF) of LNB patients. Here, we compared the performances of the Euroimmun CXCL13 enzyme-linked immunosorbent assay (CXCL13 ELISA) and the ReaScan CXCL13 lateral flow immunoassay (CXCL13 LFA), a rapid point-of-care test, to support the diagnosis of LNB. In a dual-center case-control study, CSF samples from 90 patients (34 with definite LNB, 10 with possible LNB, and 46 with other central nervous system [CNS] diseases [non-LNB group]) were analyzed with the CXCL13 ELISA and the CXCL13 LFA. Classification of patients followed the European Federation of Neurological Societies (EFNS) guidelines on LNB. The CXCL13 ELISA detected elevated CXCL13 levels in all patients with definite LNB (median, 1,409 pg/ml) compared to the non-LNB controls (median, 20.7 pg/ml; P < 0.0001), with a sensitivity of 100% and a specificity of 84.8% (cutoff value, 78.6 pg/ml; area under the receiver operating characteristic [ROC] curve, 0.93). Similarly, the CXCL13 LFA yielded elevated CXCL13 levels in 31 patients with definite LNB (median arbitrary value, 223.5) compared to the non-LNB control patients (median arbitrary value, 0; P < 0.0001) and had a sensitivity and specificity of 91.2% and 93.5%, respectively (cutoff arbitrary value, 22.5; area under the ROC curve, 0.94). The correlation between the CXCL13 levels obtained by ELISA and LFA was strong (Spearman correlation coefficient r = 0.89; P < 0.0001). The CXCL13 ELISA and the CXCL13 LFA are comparable diagnostic tools for the detection of CXCL13 in the CSF of patients with definite LNB. The advantage of the CXCL13 LFA is the shorter time to result.

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An improved detection limit and working range of lateral flow assays based on a mathematical model

The Analyst ◽

10.1039/c8an00179k ◽

2018 ◽

Vol 143 (12) ◽

pp. 2775-2783 ◽

Cited By ~ 10

Author(s):

Zhi Liu ◽

Zhiguo Qu ◽

Ruihua Tang ◽

Xiaocong He ◽

Hui Yang ◽

...

Keyword(s):

Mathematical Model ◽

Detection Limit ◽

Lateral Flow ◽

Lateral Flow Assays

The detection limit and working range of lateral flow assays are investigated experimentally and numerically.

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Development of a multiplex and sensitive lateral flow immunoassay for the diagnosis of periprosthetic joint infection

Scientific Reports ◽

10.1038/s41598-019-52051-6 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 6

Author(s):

Tsung-Ting Tsai ◽

Tse-Hao Huang ◽

Natalie Yi-Ju Ho ◽

Yu-Pei Chen ◽

Chung-An Chen ◽

...

Keyword(s):

Synovial Fluid ◽

Clinical Diagnosis ◽

Periprosthetic Joint Infection ◽

Diagnostic Tests ◽

Joint Infection ◽

Lateral Flow ◽

Rapid Response ◽

Detection Sensitivity ◽

Lateral Flow Immunoassay ◽

Enzyme Linked Immunosorbent Assay

Abstract The diagnosis of periprosthetic joint infection (PJI) remains a challenge. However, recent studies showed that synovial fluid biomarkers have demonstrated greater diagnostic accuracy than the currently used PJI diagnostic tests. In many diagnostic tests, combining several biomarkers into panels is critical for improving diagnostic efficiency, enhancing the diagnostic precision for specific diseases, and reducing cost. In this study, we prove that combining alpha-defensin and C-reactive protein (CRP) as biomarkers possesses the potential to provide accurate PJI diagnosis. To further verify the result, we developed a multi-target lateral flow immunoassay strip (msLFIA) with staking pad design to obtain on-site rapid response for clinical diagnosis of PJI. A total of 10 synovial fluid samples were tested using the msLFIA, and the results showed that the combined measurements of synovial fluid alpha-defensin and CRP levels were consistent with those obtained from a commercial enzyme-linked immunosorbent assay kit. In addition, we developed a multi-target lateral flow immunoassay strip (msLFIA) with staking pad design to obtain on-site rapid response for clinical diagnosis of PJI, which the multi-target design is used to increase specificity and the stacking pad design is to enhance detection sensitivity. As a result, the turnaround time of the highly sensitive test can be limited from several hours to 20 min. We expect that the developed msLFIA possesses the potential for routine monitoring of PJI as a convenient, low-cost, rapid and easy to use detection device for PJI.

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Urchin peroxidase-mimicking Au@Pt nanoparticles as a label in lateral flow immunoassay: impact of nanoparticle composition on detection limit of Clavibacter michiganensis

Microchimica Acta ◽

10.1007/s00604-020-04253-3 ◽

2020 ◽

Vol 187 (5) ◽

Cited By ~ 3

Author(s):

Vasily G. Panferov ◽

Irina V. Safenkova ◽

Anatoly V. Zherdev ◽

Boris B. Dzantiev

Keyword(s):

Detection Limit ◽

Pt Nanoparticles ◽

Lateral Flow ◽

Lateral Flow Immunoassay ◽

Clavibacter Michiganensis

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Serologic SARS-CoV-2 testing in healthcare workers with positive RT-PCR test or Covid-19 related symptoms

10.1101/2020.10.25.20219113 ◽

2020 ◽

Author(s):

Giovanni Visci ◽

Vittorio Lodi ◽

Roberta Bonfiglioli ◽

Tiziana Lazzarotto ◽

Francesco S. Violante ◽

...

Keyword(s):

Healthcare Workers ◽

Lateral Flow ◽

Public Hospitals ◽

Lateral Flow Immunoassay ◽

Enzyme Linked Immunosorbent Assay ◽

Limited Information ◽

Rt Pcr ◽

Positive Serology ◽

Serologic Response ◽

Pcr Test

AbstractBackgroundLimited information is available on prevalence and determinants of serologic response to SARS-CoV-2 infection among healthcare workers (HCWs).MethodsWe analyzed the results of serologic testing with chemiluminescence immunoassay analyzer (CLIA), lateral flow immunoassay (LFIA) and enzyme-linked immunosorbent assay (ELISA) test among 544 HCWs with at least one positive RT-PCR test and 157 HCWs with Covid-19 related symptoms without a positive RT-PCR test from public hospitals in Bologna, Northern Italy. Tests were performed between March and August 2020. We fitted multivariate logistic regression models to identify determinants of positive serology.ResultsThe sensitivity of SARS-CoV-2 was 75.2% (LFIA) and 90.6% (CLIA). No differences in seropositivity were observed by sex, while older HCWs had higher positivity than other groups, and nurses had higher positivity compared to physicians, but not other HCWs. An estimated 73.4% of HCWs with Covid-19 symptoms without RT-PCR test were not infected with SARS-CoV-2.ConclusionsOur study provides the best available data on sensitivity of serologic tests and on determinants of serologic response among HCWs positive for SARS-CoV-2, and provide evidence on the low specificity of Covid-19 related symptoms to identify infected HCWs.SummaryThe sensitivity of SARS-CoV-2 lateral flow immunoassay serology in healthcare workers (HCWs) was 75.2%. Older HCWs and nurses had higher positivity than other groups. An estimated 73.4% of HCWs with Covid-19 symptoms without RT-PCR test were not infected with SARS-CoV-2.

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Rapid determination of phenylethanolamine A in biological samples by enzyme-linked immunosorbent assay and lateral-flow immunoassay

Analytical and Bioanalytical Chemistry ◽

10.1007/s00216-015-8917-6 ◽

2015 ◽

Vol 407 (25) ◽

pp. 7615-7624 ◽

Cited By ~ 12

Author(s):

Xiangmei Li ◽

Wenjun Wang ◽

Limiao Wang ◽

Qi Wang ◽

Xingyao Pei ◽

...

Keyword(s):

Immunosorbent Assay ◽

Biological Samples ◽

Rapid Determination ◽

Lateral Flow ◽

Lateral Flow Immunoassay ◽

Enzyme Linked Immunosorbent Assay

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Two Orders of Magnitude Improvement in Detection Limit of Lateral Flow Assays Using Isotachophoresis

Analytical Chemistry ◽

10.1021/ac504552r ◽

2015 ◽

Vol 87 (2) ◽

pp. 1009-1017 ◽

Cited By ~ 76

Author(s):

Babak Y. Moghadam ◽

Kelly T. Connelly ◽

Jonathan D. Posner

Keyword(s):

Detection Limit ◽

Lateral Flow ◽

Lateral Flow Assays ◽

Magnitude Improvement

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Gold Nanobeads with Enhanced Absorbance for Improved Sensitivity in Competitive Lateral Flow Immunoassays

Foods ◽

10.3390/foods10071488 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1488

Author(s):

Xirui Chen ◽

Xintao Miao ◽

Tongtong Ma ◽

Yuankui Leng ◽

Liangwen Hao ◽

...

Keyword(s):

Gold Nanoparticles ◽

Detection Limit ◽

Inhibitory Concentration ◽

Fumonisin B1 ◽

Lateral Flow ◽

Detection Sensitivity ◽

Lateral Flow Immunoassay ◽

Promising Strategy ◽

Qualitative Detection ◽

Better Than

Background: Colloidal gold based lateral flow immunoassay (LFIA) commonly suffers from relatively low detection sensitivity due to the insufficient brightness of conventional gold nanoparticles (AuNPs) with the size of 20–40 nm. Methods: Herein, three kinds of gold nanobeads (GNBs) with the size of 94 nm, 129 nm, and 237 nm, were synthesized by encapsulating numerous hydrophobic AuNPs (10 nm) into polymer matrix. The synthesized GNBs exhibited the enhanced colorimetric signal intensity compared with 20–40 nm AuNPs. The effects of the size of GNBs on the sensitivity of LFIA with competitive format were assessed. Results: The results showed that the LFIA using 129 nm GNBs as amplified signal probes exhibits the best sensitivity for fumonisin B1 (FB1) detection with a cut-off limit (for visual qualitative detection) at 125 ng/mL, a half maximal inhibitory concentration at 11.27 ng/mL, and a detection limit at 1.76 ng/mL for detection of real corn samples, which are 8-, 3.82-, and 2.89-fold better than those of conventional AuNP40-based LFIA, respectively. The developed GNB-LFIA exhibited negligible cross-reactions with other common mycotoxins. In addition, the accuracy, precision, reliability, and practicability were demonstrated by determining real corn samples. Conclusions: All in all, the proposed study provides a promising strategy to enhance the sensitivity of competitive LFIA via using the GNBs as amplified signal probes.

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