کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1168097 1491148 2010 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
An aptazyme-based electrochemical biosensor for the detection of adenosine
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
An aptazyme-based electrochemical biosensor for the detection of adenosine
چکیده انگلیسی

In this work, an aptazyme-based electrochemical biosensor for the detection of adenosine is reported. Aptazyme activity was modulated by appending an “inhibitor” oligonucleotide strand containing a 32-base adenosine aptamer to the 8-17 DNAzyme. In the absence of adenosine, the DNAzyme could not form appropriate catalytic structure due to the binding with the inhibitor strand. Upon adenosine binding to the aptamer, the inhibitor strand was dissociated from the DNAzyme sequence. This allowed the DNAzyme to open and bind with the hairpin substrate, and DNAzyme activity was thereby induced, cleaving the substrate at its ribonucleotide site in the presence of Pb2+. Cleavage of the substrate yields two single-stranded products, one of which was ferrocene-tagged and acted as the signal probe. The thiolated probe modified on the gold electrode could capture the signal probe. As a result, the ferrocene (Fc) moiety was brought in close proximity to the electrode surface and the Faradaic current was observed. This electrochemical biosensor was proved to have a wide dynamic range from 5 nM to 2000 nM with a detection limit of 5 nM. The fabricated sensor is shown to exhibit high sensitivity and desirable selectivity, which might be promising for the rational construction of aptazyme-based biosensors and the determination of adenosine in clinical examination.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Analytica Chimica Acta - Volume 669, Issues 1–2, 11 June 2010, Pages 87–93
نویسندگان
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