title: Label-free and fluorescence turn-on aptasensor for protein detection via target-induced silver nanoclusters formation.
abstract: A simple turn-on and homogeneous aptasensor, which relies on target induced formation of silver nanoclusters (Ag NCs), was developed for the determination of platelet-derived growth factor B-chain homodimer (PDGF-BB). The aptasensor contains two hairpin DNA probes termed as P1 and P2. P1 consists of the aptamer sequence of PDGF-BB. Meanwhile, P2 contains the Ag NCs nucleation sequence, which is blocked by the hairpin stem region. P1 and P2 can co-exist metastably in the absence of PDGF-BB and maintain hairpin structure. However, in the presence of PDGF-BB, the binding of PDGF-BB with aptamer will result in the hybridization between P1 and P2, and release the Ag NCs nucleation sequence. In this case, Ag NCs can be formed via the reduction of Ag(+) by NaBH(4). By monitoring the increase in fluorescence intensity, we could detect the target protein with high sensitivity. The detection limit of this aptasensor is 0.37 nM, which is comparable with that of other reported aptasensors. Furthermore, this proposed aptasensor shows high selectivity toward its target protein. Thus, the proposed aptasensor based on target induced formation of Ag NCs could be used as a sensitive and selective platform for the detection of target protein.
authors.affiliation: The Key Lab of Analysis and Detection Technology for Food Safety of the MOE, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350002, PR China.
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Liu
authors.forename: Xiao-Rong
authors.initials: XR
authors.lastname: Song
authors.forename: Yi-Wei
authors.initials: YW
authors.lastname: Wang
authors.forename: Ai-Xian
authors.initials: AX
authors.lastname: Zheng
authors.forename: Guo-Nan
authors.initials: GN
authors.lastname: Chen
authors.forename: Huang-Hao
authors.initials: HH
authors.lastname: Yang
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry* / Q000378:metabolism; D000077214:Becaplermin; D055029:Inverted Repeat Sequences; D053768:Metal Nanoparticles / Q000737:chemistry*; D020574:Proto-Oncogene Proteins c-sis / Q000032:analysis; D012834:Silver / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
chemical_list: D052157:Aptamers, Nucleotide; D020574:Proto-Oncogene Proteins c-sis; D000077214:Becaplermin; D012834:Silver