title: Ultrasensitive and universal fluorescent aptasensor for the detection of biomolecules (ATP, adenosine and thrombin) based on DNA/Ag nanoclusters fluorescence light-up system.
abstract: We report here an ultrasensitive strategy based on the recognition-induced conformational alteration of aptamer and fluorescence turn-on abilities of guanine-rich (G-rich) DNA sequence in proximity to silver nanoclusters for adenosine triphosphate (ATP), adenosine (A) and thrombin (TB) detection. Herein, we designed two tailored DNA sequences noted as complementary DNA (abbreviated as c-DNA) and signal probe DNA (abbreviated as s-DNA), respectively. c-DNA is designed as a special structure consisting of a sequence complementary to aptamer at the 3'-end and a guanine-rich DNA sequence at the 5'-end; s-DNA contains a cytosine-rich sequence responsible for Ag NCs templated synthesis at the 3'-end and a link sequence (part of aptamer) complementary to partial of the c-DNA at the 5'-end. In the presence of target, the aptamer associated with the target, resulting in the formation of duplex DNA (dsDNA), the DNA-Ag NCs thereafter could close to the guanine-rich sequence, leading to enhanced fluorescence signal readout. The widespread application of the sensing system is achieved success in the detection of three biomolecules. ATP, adenosine and thrombin in the range of 0.5-8.0 μM, 0.5-7.0 μM and 50-900 nM could be linearly detected with the detection limits of 91.6 nM, 103.4 nM and 8.4 nM, respectively. This label-free and turn-on fluorescent sensing system employing the mechanism proposed here turns out to be sensitive, selective, and convenient for the detection of biomolecules without washing and separation steps.
authors.affiliation: Department of Chemistry, and Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Shanghai 200092, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Department of Chemistry, and Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Shanghai 200092, China.
authors.forename: Xiao-Chun
authors.initials: XC
authors.lastname: Hu
authors.affiliation: Department of Chemistry, and Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Shanghai 200092, China. Electronic address: shishuo@tongji.edu.cn.
authors.forename: Shuo
authors.initials: S
authors.lastname: Shi
authors.affiliation: Department of Chemistry, and Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Shanghai 200092, China.
authors.forename: Ru-Ru
authors.initials: RR
authors.lastname: Gao
authors.affiliation: Department of Chemistry, and Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Shanghai 200092, China.
authors.forename: Hai-Liang
authors.initials: HL
authors.lastname: Huang
authors.affiliation: Department of Chemistry, and Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Shanghai 200092, China.
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Zhu
authors.affiliation: Department of Chemistry, and Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Shanghai 200092, China.
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Lv
authors.affiliation: Department of Chemistry, and Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Shanghai 200092, China. Electronic address: tmyao@tongji.edu.cn.
authors.forename: Tian-Ming
authors.initials: TM
authors.lastname: Yao
mesh_terms: D000241:Adenosine / Q000302:isolation & purification*; D000255:Adenosine Triphosphate / Q000302:isolation & purification*; D052157:Aptamers, Nucleotide / Q000737:chemistry; D015374:Biosensing Techniques; D005453:Fluorescence; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry; D012834:Silver / Q000737:chemistry; D013917:Thrombin / Q000302:isolation & purification*
chemical_list: D052157:Aptamers, Nucleotide; D012834:Silver; D000255:Adenosine Triphosphate; D013917:Thrombin; D000241:Adenosine
keywords: Aptamer; DNA–Ag NCs; Fluorescence; Guanine-enhanced