title: An electrochemical DNA sensor based on polyaniline/graphene: high sensitivity to DNA sequences in a wide range.
abstract: A label-free electrochemical DNA sensor was fabricated by deposition of polyaniline and pristine graphene nanosheet (P/G(ratios)) composites in different mass ratios, DNA probe and bovine serum albumin (BSA) layer by layer on the surface of a glassy carbon electrode (GCE). Electrochemical impedance spectroscopy (EIS) was employed to monitor every step of fabrication of P/G(ratio)-based DNA sensors and to evaluate the detection results in terms of the hybridization of complementary DNA, mutant DNA and non-complementary DNA. The results illustrate that the P/G(ratio)-based DNA sensor could highly efficiently detect complementary DNA from 0.01 pm to 1 μm and discriminate single-nucleotide polymorphisms (SNPs). In the process of detection, double-stranded DNA (dsDNA), resulting from hybridization of a DNA probe, escaping from or remaining on the sensor surface, was monitored by changing the ratio of polyaniline (PANI) to graphene, which was decided by the competition between the electrostatic interaction and Brownian motion.
authors: College of Life sciences and Bioengineering, Beijing Jiaotong University, Beijing 100044, P R China. dkjian@bjtu.edu.cn.
authors: Qing
authors: Q
authors: Zheng
authors: Hao
authors: H
authors: Wu
authors: Zongxu
authors: Z
authors: Shen
authors: Wenyu
authors: W
authors: Gao
authors: Yu
authors: Y
authors: Yu
authors: Yuehui
authors: Y
authors: Ma
authors: Weijun
authors: W
authors: Guang
authors: Quangui
authors: Q
authors: Guo
authors: Rui
authors: R
authors: Yan
authors: Junzhong
authors: J
authors: Wang
authors: Kejian
authors: K
authors: Ding
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D000818:Animals; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D002417:Cattle; D004247:DNA / Q000032:analysis* / Q000737:chemistry / Q000235:genetics*; D015342:DNA Probes / Q000737:chemistry; D004563:Electrochemistry; D004579:Electron Transport; D006108:Graphite / Q000737:chemistry*; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D009693:Nucleic Acid Hybridization; D011487:Protein Conformation; D012710:Serum Albumin, Bovine / Q000737:chemistry
chemical_list: D000814:Aniline Compounds; D015342:DNA Probes; C416807:polyaniline; D012710:Serum Albumin, Bovine; D006108:Graphite; D004247:DNA