Dataset Information

Rapid detection of abrin in foods with an up-converting phosphor technology-based lateral flow assay.

ABSTRACT: Abrin is a natural plant toxin found in the seeds of Abrus precatorius. It may be used for food poisoning or bioterrorism, seriously endangering public health. In this study, a reliable method for the rapid detection of abrin in foods was developed, based on an up-converting phosphor technology-based lateral flow assay (abrin-UPT-LFA). Nine high-affinity monoclonal antibodies (mAbs) against abrin were prepared, and the optimum mAbs (mAb-6F4 and mAb-10E11) were selected for use in the assay in double-antibody-sandwich mode. The assay was confirmed to be specific for abrin, with a detection sensitivity of 0.1?ng mL^-1 for standard abrin solutions. Good linearity was observed for abrin quantitation from 0.1 to 1000?ng mL^-1 (r?=?0.9983). During the analysis of various abrin-spiked food samples, the assay showed strong sample tolerance and a satisfactory limit of detection for abrin (0.5-10?ng g^-1 for solid and powdered samples; 0.30-0.43?ng mL^-1 for liquid samples). The analysis of suspected food samples, from sample treatment to result feed-back, could be completed by non-professionals within 20?min. Therefore, the abrin-UPT-LFA is a rapid, sensitive, and reliable method for the on-site detection of abrin in foods.

SUBMITTER: Liu X

PROVIDER: S-EPMC5050493 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Rapid detection of abrin in foods with an up-converting phosphor technology-based lateral flow assay.

Liu Xiao X Zhao Yong Y Sun Chongyun C Wang Xiaochen X Wang Xinrui X Zhang Pingping P Qiu Jingfu J Yang Ruifu R Zhou Lei L

Scientific reports 20161005

Abrin is a natural plant toxin found in the seeds of Abrus precatorius. It may be used for food poisoning or bioterrorism, seriously endangering public health. In this study, a reliable method for the rapid detection of abrin in foods was developed, based on an up-converting phosphor technology-based lateral flow assay (abrin-UPT-LFA). Nine high-affinity monoclonal antibodies (mAbs) against abrin were prepared, and the optimum mAbs (mAb-6F4 and mAb-10E11) were selected for use in the assay in do ...[more]

PMID: 27703269

Similar Datasets

Project description:Methodological applications of the high sensitivity genus-specific Schistosoma CAA strip test, allowing detection of single worm active infections (ultimate sensitivity), are discussed for efficient utilization in sample pooling strategies. Besides relevant cost reduction, pooling of samples rather than individual testing can provide valuable data for large scale mapping, surveillance, and monitoring.The laboratory-based CAA strip test utilizes luminescent quantitative up-converting phosphor (UCP) reporter particles and a rapid user-friendly lateral flow (LF) assay format. The test includes a sample preparation step that permits virtually unlimited sample concentration with urine, reaching ultimate sensitivity (single worm detection) at 100% specificity. This facilitates testing large urine pools from many individuals with minimal loss of sensitivity and specificity. The test determines the average CAA level of the individuals in the pool thus indicating overall worm burden and prevalence. When requiring test results at the individual level, smaller pools need to be analysed with the pool-size based on expected prevalence or when unknown, on the average CAA level of a larger group; CAA negative pools do not require individual test results and thus reduce the number of tests.Straightforward pooling strategies indicate that at sub-population level the CAA strip test is an efficient assay for general mapping, identification of hotspots, determination of stratified infection levels, and accurate monitoring of mass drug administrations (MDA). At the individual level, the number of tests can be reduced i.e. in low endemic settings as the pool size can be increased as opposed to prevalence decrease.At the sub-population level, average CAA concentrations determined in urine pools can be an appropriate measure indicating worm burden. Pooling strategies allowing this type of large scale testing are feasible with the various CAA strip test formats and do not affect sensitivity and specificity. It allows cost efficient stratified testing and monitoring of worm burden at the sub-population level, ideally for large-scale surveillance generating hard data for performance of MDA programs and strategic planning when moving towards transmission-stop and elimination.

Project description:BackgroundTrichinella spiralis is a zoonotic food-borne parasite. A disease caused by infection with T. spiralis is called trichinellosis in humans. It is important to investigate the epidemic situation and the surveillance of herds and then prevent infection in humans. Therefore, this study is to develop a rapid and sensitive diagnostic method for on-site test in domestic and wild animals.MethodsUpconverting phosphor nanoparticles (UCNPs), an excellent optical label, were conjugated with the excretory-secretory (ES) antigens from T. spiralis muscle larvae (ML) or goat anti-rabbit IgG, and a lateral flow (LF) assay based on these probes (UCNPs-ES/goat anti-rabbit IgG) was developed for the rapid and sensitive detection of anti-T. spiralis IgG antibodies in pig serum. The assay is named the UPT-LF-ES assay. In addition, the probes were characterized, and the assay was optimized. A cut-off threshold of the assay was also identified by using 169 known negative pig samples. Performance of the assay to T. spiralis with different infective numbers, cross-reactivity with other parasitic infections, the single-blinded experiment, and coincidence were evaluated with the assay.ResultsThe UPT-LF-ES assay was successfully constructed and optimized based on the probes of UCNPs-ES/goat anti-rabbit IgG. In the pigs infected with 100, 1000, and 10,000 ML, positive results were first presented at 35 days post-infection (dpi), 30 dpi, and 25 dpi, respectively. The assay had no cross-reaction with other parasitic infections. A single-blinded experiment indicated that the sensitivity and specificity of the UPT-LF-ES assay were 100% and 100%, respectively, the area under the receiver operating characteristic (ROC) curve was 1.000. In addition, the value detected by the UPT-LF-ES assay was significantly different between positive and negative samples. Moreover, compared with the "gold standard" magnetic stirrer method, the coincidence rate of the UPT-LF-ES assay was 87.27%, and the kappa (K) coefficient was 0.7454, showing a substantial agreement.ConclusionsThe UPT-LF-ES assay is a useful point-of-care test (POCT) with T. spiralis in the detection of pig, which contributes to preventing human trichinellosis.

Project description:BackgroundQuantitative point-of-care testing assay for detecting antibodies is critical to COVID-19 control. In this study, we established an up-conversion phosphor technology-based point-of-care testing (UPT-POCT), a lateral flow assay, for rapid COVID-19 diagnosis, as well as prediction of seral neutralizing antibody (NAb) activity and protective effects.MethodsUPT-POCT was developed targeting total antibodies against the receptor-binding domain (RBD) of SARS-CoV-2 spike protein. Using ELISA as a contrast method, we evaluated the quantitation accuracy with NAb and serum samples. Cutoff for serum samples was determined through 70 healthy and 140 COVID-19 patients. We evaluated the cross-reactions with antibodies against other viruses. Then, we performed multi-center clinical trials of UPT-POCT, including 782 patients with 387 clinically confirmed COVID-19 cases. Furthermore, RBD-specific antibody levels were detected using UPT-POCT and microneutralization assay for samples from both patients and vaccinees. Specifically, the antibodies of recovered patients with recurrent positive (RP) reverse transcriptase-polymerase chain reaction test results were discussed.ResultsThe ratios of signal intensities between the test and control bands on the lateral flow strip, namely, T/C ratios, was defined as the results of UPT-POCT. T/C ratios had excellent correlations with concentrations of NAb, as well as OD values of ELISA for serum samples. The sensitivity and specificity of UPT-POCT were 89.15% and 99.75% for 782 cases in seven hospitals in China, respectively. We evaluated RBD-specific antibodies for 528 seral samples from 213 recovered and 99 RP COVID-19 patients, along with 35 seral samples from inactivated SARS-CoV-2 vaccinees, and we discovered that the total RBD-specific antibody level indicated by T/C ratios of UPT-POCT was significantly related to the NAb titers in both COVID-19 patients (r = 0.9404, n = 527; ρ = 0.6836, n = 528) and the vaccinees (r = 0.9063, ρ = 0.7642, n = 35), and it was highly relevant to the protection rate against RP (r = 0.9886, n = 312).ConclusionThis study reveals that the UPT-POCT for quantitative detection of total RBD-specific antibody could be employed as a surrogate method for rapid COVID-19 diagnosis and prediction of protective effects.

Dataset Information

Rapid detection of abrin in foods with an up-converting phosphor technology-based lateral flow assay.

Publications

Rapid detection of abrin in foods with an up-converting phosphor technology-based lateral flow assay.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets