title: Simultaneous determination of human Enterovirus 71 and Coxsackievirus B3 by dual-color quantum dots and homogeneous immunoassay.
abstract: Human Enterovirus 71 (EV71) and Coxsackievirus B3 (CVB3) have high risks for morbidity and mortality. A virus quantitation immunoassay has been proposed by employing two colored quantum dots (QDs), antibodies of the virus, and graphene oxide (GO). The QDs are streptavidin-conjugated quantum dots (SA-QDs), and the antibodies are biotinylated antibodies. Biotinylated EV71 antibody (Ab1) was associated with 525 nm green colored SA-QDs via biotin-streptavidin interaction forming QDs-Ab1, whereas biotinylated CVB3 antibody (Ab2) was associated with 605 nm red colored SA-QDs via biotin-streptavidin interaction forming QDs-Ab2. GO was an excellent quencher to the fluorescence of both QDs-Ab1 and QDs-Ab2. The targets of EV71 and CVB3 can break up the complex of QDs-Ab and GO, recovering the fluorescence of QDs-Ab1 and QDs-Ab2, respectively. Using these two different colored QDs-Ab fluorescence recovery intensities upon the addition of targets EV71 and CVB3, the two enteroviruses can be simultaneously quantitatively determined with a single excitation light. The detection limits of EV71 and CVB3 are 0.42 and 0.39 ng mL(-1) based on 3 times signal-to-noise ratio, respectively. More importantly, this strategy can be further used as a universal method for any protein or virus determination by changing the conjugated antibodies in disease early diagnosis, which can provide a fast and promising clinical approach for virus differentiation and determination. In a word, a simple, fast, sensitive, and highly selective assay for EV71 and CVB3 has been developed. It could be applied in clinical sample analysis with a satisfactory result. It was notable that the sensor could not only achieve rapid and precise quantitative determination of protein/virus by fluorescent intensity but also could be applied in semiquantitative protein/virus determination by digital visualization.
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, PR China.
authors.forename: Lu
authors.initials: L
authors.lastname: Chen
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Zhang
authors.forename: Guohua
authors.initials: G
authors.lastname: Zhou
authors.forename: Xia
authors.initials: X
authors.lastname: Xiang
authors.forename: Xinghu
authors.initials: X
authors.lastname: Ji
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Zheng
authors.forename: Zhike
authors.initials: Z
authors.lastname: He
authors.forename: Hanzhong
authors.initials: H
authors.lastname: Wang
mesh_terms: D000914:Antibodies, Viral / Q000276:immunology; D019921:Biotinylation; D003116:Color; D003429:Cross Reactions; D029821:Enterovirus A, Human / Q000276:immunology / Q000302:isolation & purification* / Q000378:metabolism; D029822:Enterovirus B, Human / Q000276:immunology / Q000302:isolation & purification* / Q000378:metabolism; D006108:Graphite / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D010087:Oxides / Q000737:chemistry; D045663:Quantum Dots; D019809:Streptavidin / Q000378:metabolism; D013997:Time Factors
chemical_list: D000914:Antibodies, Viral; D010087:Oxides; D006108:Graphite; D019809:Streptavidin