کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
185638 459601 2014 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A novel electrochemical sensor for lead ion based on cascade DNA and quantum dots amplification
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
A novel electrochemical sensor for lead ion based on cascade DNA and quantum dots amplification
چکیده انگلیسی

A new enzyme-free and ultrasensitive electrochemical Pb2+ biosensor was developed. By coupling the DNA-assisted cascade of hybridization reaction with the quantum dots (QDs) for signal amplification, a detection limit as low as 6.1 pM can be obtained for Pb2+. In this study, the “8-17” DNAzyme was used for specific recognition of Pb2+. In the presence of Pb2+, the DNAzyme was activated and cleaved the substrate strand. And then, the hybridization between the linker probe and signal probe was initiated, which resulted in formation of a long cascade DNA structure as well as assemble of numerous QDs at last. By the use of magnetic beads, the free signal probe can be easily removed by external magnetic field. After acid lysis, a great amount of redox cations can be released from the QDs and eventually result in significantly amplified electrochemical signals. This method is highly sensitive, selective and simple without the participation of any protein based enzyme (nuclease), thereby holds great potential for real sample analysis.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Electrochimica Acta - Volume 134, 10 July 2014, Pages 1–7
نویسندگان
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