کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
867249 909779 2013 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Target-induced structure-switching DNA hairpins for sensitive electrochemical monitoring of mercury (II)
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Target-induced structure-switching DNA hairpins for sensitive electrochemical monitoring of mercury (II)
چکیده انگلیسی

A simple, sensitive and reusable electrochemical sensor was designed for determination of mercury (II) (Hg2+) by coupling target-induced conformational switch of DNA hairpins with thymine–Hg2+–thymine (T–Hg2+–T) coordination chemistry. The hairpin probe consisted of a stem of 6 base pairs enclosing a 14 nucleotide (nt) loop and an additional 12 nt sticky end at the 3′ end. Each hairpin was labeled with ferrocene (Fc) redox tag in the middle of the loop, which was immobilized on the electrode via self-assembly of the terminal thiol moiety at the 5′ end. In the presence of target analyte, Hg2+-mediated base pairs induced the conformational change from the sticky end to open the hairpins, resulting in the ferrocene tags close to the electrode for the increasing redox current. The strong coordination reaction of T–Hg2+–T resulted in a good repeatability and intermediate precision down to 10%. The dynamic concentration range spanned from 5.0 nM to 1.0 μM Hg2+ with a detection limit of 2.5 nM at the 3sblank level. The strategy afforded exquisite selectivity for Hg2+ against other environmentally related metal ions. Inspiringly, the developed sensor could be reused by introduction of iodide (I−).


► DNA hairpins-based sensor for sensitive electrochemical determination of mercury (II).
► One-step electrochemical sensing of mercury (II).
► Signal-on electrochemical sensor.
► Target-induced conformational switch.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biosensors and Bioelectronics - Volume 39, Issue 1, 15 January 2013, Pages 315–319
نویسندگان
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