Voltammetric determination of underivatized oligonucleotides on graphite electrodes based on their oxidation products
Voltammetric determination of underivatized oligonucleotides on graphite electrodes based on their oxidation products
复制标题
DOI：
10.1021/ac015749m
复制
发表时间：
2002-07-15
影响因子：
7.4
通讯作者：
Tuñón-Blanco, P
中科院分区：
文献类型：
--
作者：
de-Los-Santos-Alvarez, P;Lobo-Castañón, MJ;Tuñón-Blanco, P
建立了一种测定未衍生化寡核苷酸的电化学方法。在中性或碱性介质中，吸附在热解石墨电极（PGE）上的寡核苷酸的腺嘌呤部分在升高的电位下发生电氧化，产生强烈吸附在电极表面的电活性产物。这些产物的氧化还原过程的程度，其中在pH 10下E度接近0 V（相对于Ag \AgCl），与母体寡核苷酸的量很好地相关。各种电化学技术已被比较，并应用于特定的DNA序列和合成的同源多核苷酸的检测。用10穆尔的样品体积，HIV-1的（dA）（20）和21-mer序列的检测限分别达到2和10 ng。此外，吸附的氧化寡核苷酸对NADH的氧化显示出电催化活性。新方法检测DNA杂交的能力进行了讨论。
A new electrochemical method to determine underivatized oligonucleotides is developed. The electro-oxidation of the adenine moieties of adsorbed oligonucleotides at elevated potentials on pyrolytic graphite electrodes (PGE) in neutral or alkaline media gives rise to electroactive products strongly adsorbed on the electrode surface. The extent of the redox processes of these products, with Edegrees' close to 0 V (vs Ag \AgCl) at pH 10, correlates well with the amount of parent oligonucleotide. Various electrochemical techniques have been compared and applied to the detection of specific DNA sequences and synthetic homopolynucleotides. Detection limits of 2 and 10 ng for (dA)(20) and a 21-mer sequence of HIV-1, respectively, have been achieved using sample volumes of 10 muL Moreover, the adsorbed oxidized oligonucleotide shows electrocatalytic activity toward the oxidation of NADH. The capability of the new method to detect DNA hybridization is discussed.