Ultra Sensitive Detection of Influenza A Virus Based on Cdse/Zns Quantum Dots Immunoassay

Abstract

Open Access Research articlesevere outbreaks disease, and they can cause serious infections among people.To date, numerous analytical methods have being used to detect influenza A virus. According to the type of detection target, these methods could be categorized into, for example, virus isolation and identification, nucleic acid-based detection, antigen detection, and antibody detection [3][4][5][6][7][8]. Most of these methods need demanding conditions and professional operations, and some of the detection processes is time-consuming. For these reasons, some new biosensors based on nano materials such as gold nanoparticles, magnetic nano beads and quantum dots (QDs) have been coming to the forefront [9][10][11][12].Developing a sensitive, specific and fast biosensor for diagnosing the influenza virus at the early stages of infection is a challenge. Lateral flow immune assay method has been widely used in detection of infectious diseases with the advantages of rapid, easy to operate, and low cost [13]. However, traditional method such as colloidal gold lateral flow tests has limitations when high sensitivity is needed [14].QDs have been developed to replace colloidal gold owing to their excellent optical properties such as high fluorescence efficiency, wide range of excitation wavelength, narrow and symmetric emission spectra, and QDs based lateral flow tests have been proved higher sensitivity and reproducibility for detection of pathogen, characteristic protein and even nucleic acid [15][16][17][18].In this paper, we present an ultrasensitive lateral flow immunoassay (LFIA) for detecting influenza A virus. This immune sensor is based on site-specific covalent binding with the Fc end of influenza A virus antibodies to CdSe/ ZnS QDs. The carboxylfunctionalized CdSe/ ZnS QDs conjugated with antibodies via an amide bond often result in random links of the antibody structure in the QD conjugates and block certain antigenbinding sites. In order to obtain site-specific linking, we modified carboxyl-functionalized QDs with adipicdihydrazide (ADH) and oxidized the carbohydrate groups on the antibody's Fc region AbstractAn ultrasensitive lateral flow immunoassay system (LFIAS) was established for the detection of influenza A virus. In this LFIAS, hydrophilic dihydrazide-modified CdSe/ZnSquantom dots (QDs) were conjugated with specific antibodies and used as fluorescent labels, and a pair of matched anti-nucleoprotein of influenza A virus antibodies were used to form a sandwich immunoassay. The QDs were in conjugation with the fragment crystallizable region (Fc region) of specific influenza A virus antibodies through aldehydehydrazide covalent chemistry, conferring high sensitivity. The antibodies used for detection are specific for the most conserved and popular nucleoprotein of influenza A virus and ensure the accuracy and specificity. The QDs-LFIAS can analyze the nasal-pharyngeal swab samples through simple steps and get results within 15 min. Detection of nasal-pharyngeal swab samples makes it more rapid and conve...

Recent Advances in Quantum Dot-Based Lateral Flow Immunoassays for the Rapid, Point-of-Care Diagnosis of COVID-19

“…The intensity of the fluorescent signal is proportional to the number of viral antigens present in the sample, allowing for the quantitative measurement of the infection. QD-LFIA testing offers several advantages over traditional testing methods [159,[168][169][170][171]. Firstly, it provides rapid results, usually within 15 to 30 min, allowing for quick decisionmaking and prompt patient management.…”

Quantum Dots: An Emerging Approach for Cancer Therapy

“…Consider the design, in vivo investigations using fluorescence imaging, and the life pattern of microorganisms as one of the energizing approaches (microbes, parasites, and infections). Aside from the recently developed antibacterial nano-carriers, graphene CQDs and quantum dots have shown increased utility for biosensing of organisms and may therefore be used as an optional clinical conclusion approach (Joo et al, 2008;Ma et al, 2016). The use of quantum dabs for designating the infectious envelope was demonstrated in 2008, followed by an analysis of the take-up process (Ahamed et al, 2020).…”