کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7232221 1470962 2015 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Target-regulated proximity hybridization with three-way DNA junction for in situ enhanced electronic detection of marine biotoxin based on isothermal cycling signal amplification strategy
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Target-regulated proximity hybridization with three-way DNA junction for in situ enhanced electronic detection of marine biotoxin based on isothermal cycling signal amplification strategy
چکیده انگلیسی
A new signal amplification strategy based on target-regulated DNA proximity hybridization (TRPH) reaction accompanying formation of three-way DNA junction was designed for electronic detection of Microcystin-LR (MC-LR used in this case), coupling with junction-induced isothermal cycling signal amplification. Initially, a sandwiched-type immunoreaction was carried out in a low-cost PCR tube between anti-MC-LR mAb1 antibody-labeled DNA1 (mAb1-DNA1) and anti-MC-LR mAb2-labeled DNA2 (mAb2-DNA2) in the presence of target to form a three-way DNA junction. Then, the junction could undergo an unbiased strand displacement reaction on an h-like DNA nanostructure-modified electrode (labeled with methylene blue redox tag on the short DNA strand), thereby resulting in the dissociation of methylene blue-labeled signal DNA from the electrode. The newly formed double-stranded DNA could be cleaved again by exonuclease III, and the released three-way DNA junction retriggered the strand-displacement reaction with h-like DNA nanostructures for junction recycling. During the strand-displacement reaction, numerous methylene blue-labeled DNA strands were far away from the electrode, thus decreasing the detectable electrochemical signal within the applied potentials. Under optimal conditions, the TRPH-based immunosensing system exhibited good electrochemical responses for detecting target MC-LR at a concentration as low as 1.0 ng kg−1 (1.0 ppt). Additionally, the precision, reproducibility, specificity and method accuracy were also investigated with acceptable results.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biosensors and Bioelectronics - Volume 69, 15 July 2015, Pages 241-248
نویسندگان
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