Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
Bioelectrochemistry. 2010 Jun;78(2):141-6. doi: 10.1016/j.bioelechem.2009.09.004. Epub 2009 Sep 14.
A new electrochemical DNA biosensor is presented based on carbon past electrode (CPE) for immobilization and detection of short DNA sequences with brilliant cresyl blue (BCB) as electroactive label. The interaction of BCB with DNA is electrochemically detected and BCB displays different signals in the interaction to ssDNA and dsDNA and variation in the BCB signal represents the extent of hybridization at the electrode surface. The effect of solution pH on electrochemical behavior of BCB was investigated. Additionally, the effect of solution pH on BCB accumulation on the CPE was studied. Furthermore, experiments showed that the solution pH could influence the differential pulse voltammetry (DPV) signal of BCB accumulated on the electrode and the highest BCB signal was obtained in pH 7.00. The effect of electrochemical pretreatment of CPE on the ability of electrode in probe adsorption, BCB accumulation and conditions of probe immobilization including potential and time was investigated and optimum conditions were suggested. The peak currents of BCB were linearly related to the concentration of the target oligonucleotide sequence in the range of 1.0x10(-8) to 5.0x10(-6)M. The detection limit of this approach was 9.00nM. The selectivity of the biosensor was studied using noncomplementary oligonucleotide.
一种新的电化学 DNA 生物传感器是基于碳糊电极（CPE）为固定和检测短 DNA 序列与灿烂的甲酚蓝（BCB）作为电活性标记。BCB 与 DNA 的相互作用是电化学检测和 BCB 显示不同的信号在相互作用，以单链 DNA 和双链 DNA 和 BCB 信号的变化代表杂交的程度在电极表面。溶液 pH 值对 BCB 电化学行为的影响进行了研究。此外，还研究了溶液 pH 值对 CPE 上 BCB 积累的影响。此外，实验表明，溶液 pH 值可以影响电极上积累的 BCB 的差分脉冲伏安法（DPV）信号，在 pH 7.00 时获得最高的 BCB 信号。研究了 CPE 的电化学预处理对电极探针吸附、BCB 积累和探针固定条件（包括电位和时间）的能力的影响，并提出了最佳条件。BCB 的峰电流与目标寡核苷酸序列在 1.0x10（-8）至 5.0x10（-6）M 的浓度范围内呈线性关系。该方法的检测限为 9.00nM。使用非互补寡核苷酸研究了生物传感器的选择性。
