title: Detection of adenosine using surface-enhanced Raman scattering based on structure-switching signaling aptamer.
abstract: In the present study, we report a novel sensitive method for the detection of adenosine using surface-enhanced Raman scattering (SERS) sensing platform based on a structure-switching aptamer. First, Ag-clad Au colloids film on a polished gold disc is prepared as enhanced substrate and modified with thiolated capture DNA. The formation of an aptamer/DNA duplex of expanded anti-adenosine aptamer and tetramethylrhodamine-labeled DNA (denoted TMR-DNA) is then developed, in which TMR-DNA could also hybridize completely with capture DNA. The introduction of adenosine thus triggers structure switching of the aptamer from aptamer/DNA duplex to aptamer/target complex. As a result, the released TMR-DNA is captured onto the SERS substrate, resulting in an increase of SERS signal. Under optimized assay conditions, a wide linear dynamic range (2.0 x 10(-8)M to 2 x 10(-6)M) was reached with low detection limit (1.0 x 10(-8)M). Moreover, high selectivity, stability and facile regeneration are achieved. The successful test demonstrates the feasibility of the strategy for adenosine assay.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, PR China.
authors.forename: Ji-Wei
authors.initials: JW
authors.lastname: Chen
authors.forename: Xue-Ping
authors.initials: XP
authors.lastname: Liu
authors.forename: Ke-Jun
authors.initials: KJ
authors.lastname: Feng
authors.forename: Yi
authors.initials: Y
authors.lastname: Liang
authors.forename: Jian-Hui
authors.initials: JH
authors.lastname: Jiang
authors.forename: Guo-Li
authors.initials: GL
authors.lastname: Shen
authors.forename: Ru-Qin
authors.initials: RQ
authors.lastname: Yu
mesh_terms: D000241:Adenosine / Q000032:analysis*; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry; D012680:Sensitivity and Specificity; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D052157:Aptamers, Nucleotide; D006046:Gold; D000241:Adenosine