Journal
ANALYTICAL CHEMISTRY
Volume 83, Issue 20, Pages 8035-8040Publisher
AMER CHEMICAL SOC
DOI: 10.1021/ac2019552
Keywords
-
Categories
Funding
- National Natural Science Foundation of China [20890020, 20820102037, 20935003, 21055116]
- 973 projects [2009CB930100, 2010CB933600, 2011CB911002]
Ask authors/readers for more resources
Taking advantage of strand-displacement DNA polymerization and parallel-motif DNA triplex system as dual amplifications, a new electrochemical label-free integrated aptasensor based on silver microspheres (SMSs) as a separation element and graphene-mesoporous silica-gold nanoparticle (NP) hybrids (GSGHs) as an enhanced element of the sensing platform was first reported. In this sensing design (schematic representation of the sensing procedure for adenosine triphosphate detection, Scheme 1 in manuscript text), which contains an enhanced three-step magnification process, SMSs with clean surface were first used to separate the undesirable aptamer and aptamer-adenosine triphosphate (ATP) complex attached on SMSs surface after aptamer-ATP interaction, which lead to the detachment of blocker DNA into the solution phase. Then, under the assistance of blocker DNA, an amplified method based on the inherent signal-transduction mechanism of the hairpin probe and strand-displacement property of DNA polymerase was introduced. The obtained duplex DNA was used to hybridize with an acceptor DNA assembled on electrode to form triplex DNA, which could bring a more obvious detection signal compared with the duplex DNA without the amplification. The electrochemical signal came from the GSGH-based enhanced sensing interface containing positively charged ferrocene-appended poly(ethyleneimine) (Fc-PEI). Using the above multiple effects, we could achieve the sensitive analysis of a model small molecule-ATP (an important molecular currency of intracellular energy transfer) in a wide detection range from 0.05 nM to 56.5 nM with the detection limit of 0.023 nM.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available