Rapid lateral flow immunoassay for the fluorescence detection of SARS-CoV-2 RNA

Electrochemical immunosensor platform based on gold-clusters, cysteamine and glutaraldehyde modified electrode for diagnosing COVID-19

“…After emerging from Wuhan in China’s Hubei Province, the coronavirus disease 2019 (COVID-19), beginning as severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), rapidly spread to more than 100 countries. SARS-CoV-2, a member of the genus Betacoronavirus , has oval structure and a size ranging from 60 nm to 140 nm [1] . As of 23 February 2021, more than 110 million cumulative cases of COVID-19 and 2.4 million deaths had been reported worldwide [2] .…”

“…Many methods of diagnosing COVID-19 have been reported, including ones based on real-time polymerase chain reaction (RT-PCR) [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , lateral flow assay (LFA) [15] , lateral flow immunoassay (LFIA) [1] , [16] , [17] , [18] , [19] enzyme-linked immunosorbent assay (ELISA) [20] , plasmonic sensors [21] , [22] computed tomography (CT) imaging [23] and electrochemical biosensing technologies [3] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] . Despite being the primary and most sensitive and selective method of diagnosing COVID-19, RT-PCR is time-consuming and expensive, requires qualified personnel and can be run only in laboratory-based medical institutions [3] , [8] , [25] , [26] .…”

Rigid monoclonal antibodies improve detection of SARS-CoV-2 nucleocapsid protein

“…However, there is an urgent need to improve the detection limit of these diagnostic devices that use various types of colorimetric mAb-based assays (Alpdagtas et al, 2020). Multiple approaches, like florescent immunoassays (Ahn et al, 2009;Loeffelholz & Tang, 2020;Wang et al, 2020), nanoparticle luminescence (Hesari & Ding, 2020;Teengam et al, 2017) or magnetic beads as the antibody support surface (Fabiani et al, 2021), are used to enhance the detection of antigen. In immunoassays and RT-PCR, the detection is signaled through chemical conjugation to an enzyme or nanoparticle that drives a colorimetric reaction, a fluorophore, or another moiety.…”

Paper-Based Biosensors: Frontiers in Point-of-Care Detection of COVID-19 Disease

“…In this context, Wang et al [101] presented an amplification-free, rapid and easy method for SARS-CoV-2 nucleic acid detection, usable at the POC. It is basically a nucleic acid immunoassay, implemented on a lateral flow strip (NALFIA) for fluorescence detection of viral RNA in less than 1 hour.…”