کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
180766 459388 2009 4 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Oligonucleotides-based biosensors with high sensitivity and selectivity for mercury using electrochemical impedance spectroscopy
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Oligonucleotides-based biosensors with high sensitivity and selectivity for mercury using electrochemical impedance spectroscopy
چکیده انگلیسی

A novel electrochemical biosensor with high sensitivity and selectivity for mercuric ion detection, based on DNA self-assembly electrode, is designed. Thiol functionalized poly-T oligonucleotides were used as gold electrode modifier through formation of Au–S bond between DNA and gold electrode. In presence of Hg2+ ions, the specific coordination between Hg2+ and thymine bases can change parallel ss-DNA from linear to hairpin structures, which can cause the release of partial DNA molecules from the surface of the electrode. The density of DNA on the surface of electrode correlated with the concentration of mercury in the solution and can be monitored by electrochemical impedance spectroscopy. The limit of detection of this method is pM level of mercuric ions which is far below the upper limit of Hg2+ mandated by United States Environmental Protection Agency (EPA), 2 ppb (10 nM). In addition, this method showed excellent selectivity. A series of divalent metal ions, including Ni2+, Co2+, Mg2+, Zn2+, Ba2+ and Cd2+, have little interference with the detection of Hg2+.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Electrochemistry Communications - Volume 11, Issue 9, September 2009, Pages 1815–1818
نویسندگان
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