Quantum dot-based lateral-flow immunoassay for rapid detection of rhein using specific egg yolk antibodies

Abstract

The lateral-flow immunoassays based on novel fluorescent labels have been receiving increasing attention. Here, we developed a rapid, quantitative, lateral-flow immunoassay for rapid and accurate detection of rhein (RHE). The competitive immunoassay used anti-RHE IgY (immunoglobulin of yolk) probe conjugated with QDs as reporter. Our results showed that the immunochromatographic strip can be applied for qualitative and quantitative analysis of RHE in samples. For quantitative analysis, the strips were scanned by a membrane-strip reader, and a detection curve (y = -0.128ln(x) + 1.7627, correlation coefficient = 0.9792) representing the averages of the scanned data was obtained. The detection range was 80-5000 ng mL and the qualitative-detection limit for RHE was 98.2 ng mL. To our knowledge, this is the first report of the quantitative detection of a natural product by QDs-IgY immunochromatography, which creates a new strategy to detect the harmful or index component of TCM and may be applied as a supplement or alternative to instrument detection.

Egg yolk antibodies (IgY) and their applications in human and veterinary health: A review

“…The potential of IgY in identifying substances has also been used to evaluate the toxicity of a natural product employed in the alternative medicine. IgY labeled with Quantum dot were successfully used in a lateral flow assay for the detection of rhein; a toxic substance found in the plant Rheum officinale, widely used in Chinese traditional medicine; in plant samples and serum from users [125].…”

A Group of Complexes Based on PAMAM and Quantum Dots Used in Clinical Immunoassays

“…The QDs' part is a QDs-conjugated goat anti-mouse IgG. Antibody-conjugated QDs are usually formed by cross-coupling reactions, where antibody molecules bind to functional groups such as carboxyl groups or amino groups on the QDs' surface [13,14]. In this study, we used core/shell CdSe/ZnS water-soluble quantum dots stabilized with carboxyl ligands and the carbodiimide coupling reaction using EDC (1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride).…”

Six decades of lateral flow immunoassay: from determining metabolic markers to diagnosing COVID-19

“…The etiological cause of the 2019 pandemic was the new SARS-CoV-2 virus (Severe acute respiratory syndrome coronavirus 2), which in half a year caused hundreds of thousands of deaths and caused disease in millions of the world's inhabitants, caused chaos and a drop in the level of the world economy, and in the world community–fear and anxiety for the future of mankind. According to a WHO report, as of July 1, 2020, the number of COVID-19 cases in the world exceeded 10 million, and the quantity of deaths was over 500 thousand [90] .…”

“…One of the most important directions in the strategy of combating a new infection has become the need for mass laboratory screening of populations at high risk of infection. The need for timely and high-quality laboratory diagnosis of patients infected with SARS-CoV-2 has become the main priority in eliminating the pandemic and introducing quarantine measures [87] , [90] , [96] , [97] .…”