A magnetic-enhanced FRET biosensor for simultaneous detection of multiple antibodies

• Published in: Smart materials in medicine Vol. 5; no. 2; pp. 196 - 206
• Main Authors: Li, Lihua, Lu, Yao, Lao, Xinyue, Pang, Sin-Yi, Song, Menglin, Wong, Man-Chung, Wang, Feng, Yang, Mo, Hao, Jianhua
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.06.2024; KeAi Communications Co., Ltd
• Subjects: IgG and IgM detection; Magnetic nanocrystals; Multicolor detection; SARS-CoV-2 antibodies; Upconversion nanoparticles; IgG and IgM detection; SARS-CoV-2 antibodies; Magnetic nanocrystals; Multicolor detection; Upconversion nanoparticles
• ISSN: 2590-1834; 2590-1834
• DOI: 10.1016/j.smaim.2023.12.003

Accurate, rapid and sensitive detection of specific immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies in human samples is crucial for preventing and assessing pandemics, especially in the case of recent COVID-19 outbreaks. However, simultaneous and efficient detection of IgG and IgM in a single system remains challenging. Herein, we developed a multicolor nanosystem capable of quantitatively analyzing anti-SARS-CoV-2 IgG and IgM with high sensitivity within 20 ​min. The detection system consists of core-shell upconversion nanoparticles (csUCNPs), secondary antibodies labeled with fluorescent dyes (sab), and magnetic nanocrystals (PMF). By leveraging the Förster resonance energy transfer (FRET) effect, the photoluminescence (PL) intensity of blue and green regions is restored for IgG and IgM detection, respectively. Inspiringly, owing to the introducing of PMF, the limits of detection (LODs) of IgG and IgM tested are improved to 89 ​fmol ​L−1 and 19.4 ​fmol ​L−1, representing about 416-folds and 487-folds improvement over only-dye dependent system, respectively. Mechanistic investigations reveal that the high collective effect and surface energy transfer efficiency from csUCNPs to PMF contribute to the enhanced detection sensitivity. The assay enables us to quantify clinical vaccinated samples with high specificity and precision, suggesting our multicolor platform can be a promising alternative for clinical point-of-care serological assay. [Display omitted] •A multicolor nanosystem for simultaneous analysis of IgG and IgM was established.•The brought of MnFe2O4 NPs could significantly amplify the detection sensitivity.•The system shows high accuracy and specificity in the detection of clinical samples.