Label-free electrochemical DNA biosensor array for simultaneous detection of the HIV-1 and HIV-2 oligonucleotides incorporating different hairpin-DNA probes and redox indicator.
Label-free electrochemical DNA biosensor array for simultaneous detection of the HIV-1 and HIV-2 oligonucleotides incorporating different hairpin-DNA probes and redox indicator.
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DOI：
10.1016/j.bios.2009.09.032
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发表时间：
2010-01
影响因子：
12.6
通讯作者：
Dongdong Zhang;Yage Peng;H. Qi;Q. Gao;Chengxiao Zhang
中科院分区：
文献类型：
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作者：
Dongdong Zhang;Yage Peng;H. Qi;Q. Gao;Chengxiao Zhang
开发了一种无标记的电化学DNA生物传感器阵列，作为使用微升样品同时检测多重DNA的模型系统。采用金溅射技术制备了6个金工作电极和1个金辅助电极，并采用丝网印刷技术制备了印刷Ag/AgCl参比电极。将两种巯基化的发夹DNA探针分别自组装到相应的三个工作电极表面，构建了同时检测人类免疫缺陷病毒（HIV）寡核苷酸序列HIV-1和HIV-2的DNA生物传感器阵列。以亚甲基蓝（MB）为氧化还原指示剂，采用方波伏安法监测杂交过程。由于MB对单链DNA的亲和力高于对双链DNA的亲和力，因此MB在阵列上积累的氧化电流随着HIV浓度的增加而降低。在优化条件下，HIV-1和HIV-2的峰电流在20 ~ 100 nM范围内呈线性关系，检出限均为0.1nM（S/N=3）。该传感器阵列具有良好的特异性，无明显的交叉干扰。此外，单碱基突变寡核苷酸和随机寡核苷酸可以容易地与互补靶DNA区分开。这项工作表明，不同的发夹-DNA探针可用于设计的无标记的电化学生物传感器阵列的同时检测多重DNA序列的各种临床应用。
A label-free electrochemical DNA biosensor array was developed as a model system for simultaneous detection of multiplexed DNAs using microlitres of sample. A novel multi-electrode array was comprised of six gold working electrodes and a gold auxiliary electrode, which were fabricated by gold sputtering technology, and a printed Ag/AgCl reference electrode was fabricated by screen-printing technology. The DNA biosensor array for simultaneous detection of the human immunodeficiency virus (HIV) oligonucleotide sequences, HIV-1 and HIV-2, was fabricated in sequence by self-assembling each of two kinds of thiolated hairpin-DNA probes onto the surfaces of the corresponding three working electrodes, respectively. The hybridization events were monitored by square wave voltammetry using methylene blue (MB) as a hybridization redox indicator. The oxidation currents of MB accumulated on the array decreased with increasing the concentration of HIVs due to higher affinity of MB for single strand rather than double strands of DNA. Under the optimized conditions, the peak currents were linear over ranges from 20 to 100nM for HIV-1 and HIV-2, with the same detection limits of 0.1nM (S/N=3), respectively. The biosensor array showed a good specificity without the obvious cross-interference. Furthermore, single-base mutation oligonucleotides and random oligonucleotides can be easily discriminated from complementary target DNAs. This work demonstrates that different hairpin-DNA probes can be used to design the label-free electrochemical biosensor array for simultaneous detection of multiplexed DNA sequences for various clinical applications.