title: Graphene oxide based fluorescent aptasensor for adenosine deaminase detection using adenosine as the substrate.
abstract: We present a novel fluorescent aptasensor for simple and accurate detection of adenosine deaminase (ADA) activity and inhibition on the basis of graphene oxide (GO) using adenosine (AD) as the substrate. This aptasensor consists of a dye-labeled single-stranded AD specific aptamer, GO and AD. The fluorescence intensity of the dye-labeled AD specific aptamer is quenched very efficiently by GO as a result of strong π-π stacking interaction and excellent electronic transference of GO. In the presence of AD, the fluorescence of the GO-based probe is recovered since the competitive binding of AD and GO with the dye-labeled aptamer prevents the adsorption of dye-labeled aptamer on GO. When ADA was introduced to this GO-based probe solution, the fluorescence of the probe was quenched owing to ADA can convert AD into inosine which has no affinity to the dye-labeled aptamer, thus allowing quantitative investigation of ADA activity. The as-proposed sensor is highly selective and sensitive for the assay of ADA activity with a detection limit of 0.0129U/mL in clean buffer, which is more than one order of magnitude lower than the previous reports. Meanwhile, a good linear relationship with the correlation coefficient of R=0.9922 was obtained by testing 5% human serum containing a series of concentrations of ADA. Additionally, the inhibition effect of erythro-9-(2-hydroxy-3-nonyl) adenine on ADA activity was investigated in this design. The GO-based fluorescence aptasensor not only provides a simple, cost-effective and sensitive platform for the detection of ADA and its inhibitor but also shows great potential in the diagnosis of ADA-relevant diseases and drug development.
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Research Center for Nanobiology and Nanomedicine (MOE 985 Innovative Platform), Wuhan Institute of Biotechnology, and State Key Laboratory of Virology, Wuhan University, Wuhan 430072, China.
authors.forename: Xiao-Jing
authors.initials: XJ
authors.lastname: Xing
authors.forename: Xue-Guo
authors.initials: XG
authors.lastname: Liu
authors.lastname: Yue-He
authors.forename: Qing-Ying
authors.initials: QY
authors.lastname: Luo
authors.forename: Hong-Wu
authors.initials: HW
authors.lastname: Tang
authors.forename: Dai-Wen
authors.initials: DW
authors.lastname: Pang
mesh_terms: D000241:Adenosine / Q000378:metabolism*; D000243:Adenosine Deaminase / Q000097:blood* / Q000378:metabolism; D058892:Adenosine Deaminase Inhibitors / Q000494:pharmacology; D052157:Aptamers, Nucleotide / Q000737:chemistry* / Q000378:metabolism; D015374:Biosensing Techniques / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry* / Q000378:metabolism; D006108:Graphite / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D057230:Limit of Detection; D008958:Models, Molecular; D010087:Oxides / Q000737:chemistry / Q000378:metabolism; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D058892:Adenosine Deaminase Inhibitors; D052157:Aptamers, Nucleotide; D005456:Fluorescent Dyes; D010087:Oxides; D006108:Graphite; D000243:Adenosine Deaminase; D000241:Adenosine