|
Type |
Poster Presentation |
Area |
Electrochemistry |
Room No. |
Event Hall |
Time |
4월 20일 (금요일) 11:00~12:30 |
Code |
ELEC.P-588 |
Subject |
Ultrasensitive Electrochemical Detection of miRNA-21 Using a Zinc Finger Protein |
Authors |
Chiew San Fang, Haesik Yang* Department of Chemistry, Pusan National University, Korea |
Abstract |
Both high sensitivity and high specificity are crucial for detection of miRNAs that have emerged as important clinical biomarkers. Just Another Zinc finger proteins (JAZ, ZNF346) bind preferably (but nonsequence-specifically) to DNA− RNA hybrids over single-stranded RNAs, single-stranded DNAs, and double-stranded DNAs. We present an ultrasensitive and highly specific electrochemical method for miRNA-21 detection based on the selective binding of JAZ to the DNA−RNA hybrid formed between a DNA capture probe and a target miRNA-21. This enables us to use chemically stable DNA as a capture probe instead of RNA as well as to apply a standard sandwich-type assay format to miRNA detection. High signal amplification is obtained by (i) enzymatic amplification by alkaline phosphatase (ALP) coupled with (ii) electrochemical-chemical-chemical (ECC) redox cycling involving an ALP product (hydroquinone). Low nonspecific adsorption of ALP-conjugated JAZ is obtained using a polymeric self-assembled-monolayer-modified and casein-treated indium−tin oxide electrode. The detection method can discriminate between target miRNA-21 and nontarget nucleic acids (DNA−DNA hybrid, single-stranded DNA, miRNA-125b, miRNA-155, single-base mismatched miRNA, and three-base mismatched miRNA). The detection limits for miRNA-21 in buffer and 10-fold diluted serum are approximately 2 and 30 fM, respectively, indicating that the detection method is ultrasensitive. This detection method can be readily extended to multiplex detection of miRNAs with only one ALP-conjugated JAZ probe due to its nonsequence-specific binding character. We also believe that the method could offer a promising solution for point-of-care testing of miRNAs in body fluids. |
E-mail |
susanfang_1988@hotmail.com |
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