Introduction of graphene oxide-supported multilayer-quantum dots nanofilm into multiplex lateral flow immunoassay: A rapid and ultrasensitive point-of-care testing technique for multiple respiratory viruses

Abstract

A lateral flow immunoassay (LFA) biosensor that allows the sensitive and accurate identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other common respiratory viruses remains highly desired in the face of the coronavirus disease 2019 pandemic. Here, we propose a multiplex LFA method for the on-site, rapid, and highly sensitive screening of multiple respiratory viruses, using a multilayered film-like fluorescent tag as the performance enhancement and signal amplification tool. This film-like three-dimensional (3D) tag was prepared through the layer-by-layer assembly of highly photostable CdSe@ZnS−COOH quantum dots (QDs) onto the surfaces of monolayer graphene oxide nanosheets, which can provide larger reaction interfaces and specific active surface areas, higher QD loads, and better luminescence and dispersibility than traditional spherical fluorescent microspheres for LFA applications. The constructed fluorescent LFA biosensor can simultaneously and sensitively quantify SARS-CoV-2, influenza A virus, and human adenovirus with low detection limits (8 pg/mL, 488 copies/mL, and 471 copies/mL), short assay time (15 min), good reproducibility, and high accuracy. Moreover, our proposed assay has great potential for the early diagnosis of respiratory virus infections given its robustness when validated in real saliva samples. Electronic Supplementary Material Supplementary material (Section S1 Experimental section, Section S2 Calculation of the maximum number of QDs on the GO@TQD nanofilm, Section S3 Optimization of the LFA method, and Figs. S1–S17 mentioned in the main text) is available in the online version of this article at 10.1007/s12274-022-5043-6.

Development of a Fluorescent Immunochromatographic Assay Based on Quantum Dot-Functionalized Two-Dimensional Monolayer Ti3C2 MXene Nanoprobes for the Simultaneous Detection of Influenza A Virus and SARS-CoV-2

“…Such data set outcomes indicated that Ti 3 C 2 -QD-ICA had a high sensitivity and good colorimetric performance for concomitantly detecting H1N1 and SARS-CoV-2 real viruses. The method was compared with other recently reported biosensors in terms of sensitivity, reproducibility, specificity, and assay time in Table S1. ,,− Our method demonstrated a relatively superior assay performance among these assays. The Ti 3 C 2 -QD-ICA has the potential to be a valuable POCT instrument focusing upon accurate and rapid clinical determination of respiratory viruses because of its good stability, multiplex detection capability, easy operation, cheap cost, and short detection time.…”

Introduction of a multilayered fluorescent nanofilm into lateral flow immunoassay for ultrasensitive detection of Salmonella typhimurium in food samples

“…Very recently, two-dimensional nanomaterials, such as graphene oxide (GO), titanium carbide, black phosphorus, and molybdenum disulde, have been used as excellent carriers for the construction of ultrasensitive biosensors due to their massive surface areas, exibility, superior stability, and abundant surface groups. [31][32][33] Our previous works also demonstrated the combination of monolayer GO and other nanoparticles (e.g., QDs, AuNPs, and AgNPs) as high-performance lm-like nanotags for LFIA methods. [34][35][36] For example, the GO nanosheet loaded one layer of dense QDs can act as exible uorescent tags for simultaneous detection of two kinds respiratory pathogens in real respiratory tract samples via LFIA strip.…”

Introduction of Multilayered Dual-Signal Nanotags into a Colorimetric-Fluorescent Coenhanced Immunochromatographic Assay for Ultrasensitive and Flexible Monitoring of SARS-CoV-2

“…As a result of its distinct characteristics, including low cost, good robustness, simplicity, and convenience, the immunochromatographic assay (ICA) has been regarded as the most popular and mature rapid detection technology and is widely used in infectious disease diagnosis and identification of various pathogens. − Traditional ICA methods, which are based on colloidal AuNPs to output visual colorimetric signals, have two shortcomings, namely, lack of sensitivity and poor quantitative capacity to be solved. − To improve the performance of ICA, researchers have recently introduced novel signal tags, such as fluorescent microspheres, quantum dots (QDs), magnetic particles, surface-enhanced Raman scattering (SERS) tags, and nanoenzyme tags to replace traditional AuNPs and provide more sensitive and readable signals (fluorescence, magnetic, SERS, and chemiluminescence) for quantitative detection. − However, these novel ICA biosensors usually need large or precision instruments and lack visual detecting performance, which weakens the on-site detection ability of immunochromatography.…”