title: Aptasensor for amplified IgE sensing based on fluorescence quenching by graphene oxide.
abstract: Water-soluble graphene oxide (GO) with a two-dimensional layered nanostructure was synthesized and used as a quencher to construct a highly sensitive and selective fluorescence resonance energy transfer (FRET) aptasensor for sensing Immunoglobulin E (IgE). The fluorescein isothiocyanate (FITC)-labeled aptamer could be adsorbed stably onto the surface of GO via π → π stacking interaction, which led to the occurrence of FRET from FITC to GO, and the fluorescence of FITC-labeled aptamer was quenched by GO via energy transfer. In the presence of IgE, the fluorescence was recovered due to a higher affinity between the aptamer and IgE compared with interactions between GO and the aptamer, leading to a high signal-to-background ratio. The fluorescence intensity of the aptamer increased in proportion to the amount of IgE in the sample,so that IgE could be detected with a linear range of 60-225 pM and a detection limit of 22 pM. The assay was highly selective because the aptamer was unaffected by the presence of immunoglobulin G (IgG), human serum albumin (HSA) and bovine serum albumin (BSA). The practical application of the proposed aptasensor was successfully carried out for the determination of IgE in human serum samples.
authors.affiliation: Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education), College of Chemistry and Chemical Engineering, Guangxi Normal University, Guilin, 541004, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Hu
authors.forename: Hu
authors.initials: H
authors.lastname: Yang
authors.forename: Jia
authors.initials: J
authors.lastname: Zhou
authors.forename: Shulin
authors.initials: S
authors.lastname: Zhao
authors.forename: Jianniao
authors.initials: J
authors.lastname: Tian
mesh_terms: D000327:Adsorption; D000818:Animals; D002417:Cattle; D005453:Fluorescence; D031541:Fluorescence Resonance Energy Transfer; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D007073:Immunoglobulin E / Q000032:analysis*; D017879:Isothiocyanates / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D012709:Serum Albumin / Q000032:analysis; D013499:Surface Properties
chemical_list: D017879:Isothiocyanates; D010087:Oxides; D012709:Serum Albumin; C037152:isothiocyanic acid; D007073:Immunoglobulin E; D006108:Graphite