Benvidi Ali, Abbasi Zohreh, Dehghan Tezerjani Marzieh, Banaei Maryam, Zare Hamid Reza, Molahosseini Hossein, Jahanbani Shahriar
Acta Chim Slov. 2018 Jun;65(2):278-288. doi: 10.17344/acsi.2017.3667.
In this study, a simple and novel electrochemical biosensor based on a glassy carbon electrode (GCE) modified with a composite of graphene oxide (GO) - silk fibroin nanofibers (SF) and gold nanoparticles (MCH/ssDNA/AuNPs/SF/GO/GCE) was developed for detection of DNA sequences. The fabrication processes of electrochemical biosensor were characterized by scanning electron microscopy (SEM), FT-IR and electrochemical methods. Some experimental conditions such as immobilization time of probe DNA and MCH incubation time, time and temperature of hybridization were optimized. The designed biosensor revealed a wide linear range of 1.0 × 10-16 - 1.0 × 10-8 mol L-1 and a low detection limit (3.3 × 10-17 mol L-1) for detection of BRCA1 5382 mutation by EIS technique. The designed biosensor revealed high selectivity for discrimination of the complementary (P1C) sequences from various non-complementary sequences of (P1nC1, P1nC2 and P1nC3). Also, the biosensor revealed a high reproducibility (RSD of 7.5% (n=4)) and high stability (92% of its initial response after 8 days). So, the fabricated biosensor has a suitable potential to be applied for detection of breast cancer sequences in the initial stages of the cancer.
在本研究中，开发了一种基于修饰有氧化石墨烯（GO）-丝素蛋白纳米纤维（SF）和金纳米颗粒复合材料的玻碳电极（GCE）的简单新颖的电化学生物传感器（MCH/ssDNA/AuNPs/SF/GO/GCE）用于检测DNA序列。采用扫描电子显微镜（SEM）、傅里叶变换红外光谱（FT-IR）和电化学方法对电化学生物传感器的制备过程进行了表征。对一些实验条件进行了优化，如探针DNA的固定时间、MCH孵育时间、杂交时间和温度。所设计的生物传感器通过电化学阻抗谱（EIS）技术检测BRCA1 5382突变时，显示出1.0×10-16 - 1.0×10-8 mol L-1的宽线性范围和低检测限（3.3×10-17 mol L-1）。所设计的生物传感器对互补序列（P1C）与各种非互补序列（P1nC1、P1nC2和P1nC3）具有高选择性。此外，该生物传感器具有高重现性（相对标准偏差为7.5%（n=4））和高稳定性（8天后其初始响应的92%）。因此，所制备的生物传感器具有适用于在癌症初始阶段检测乳腺癌序列的潜力。
