title: An electrochemical biosensor based on DNA tetrahedron/graphene composite film for highly sensitive detection of NADH.
abstract: Dihydronicotinamide adenine dinucleotide (NADH) is a major biomarker correlated with lethal diseases such as cancers and bacterial infection. Herein, we report a graphene-DNA tetrahedron-gold nanoparticle modified gold disk electrode for highly sensitive NADH detection. By assembling the DNA tetrahedron/graphene composite film on the gold disk electrode surface which prior harnessed electrochemical deposition of gold nanoparticles to enhance the effective surface area, the oxidation potential of NADH was substantially decreased to 0.28V (vs. Ag/AgCl) and surface fouling effects were successfully eliminated. Furthermore, the lower detection limit of NADH by the presented platform was reduced down to 1fM, with an upper limit of 10pM. Both the regeneration and selectivity of composite film-modified electrode are investigated and proved to be robust. The novel sensor developed here could serve as a highly sensitive probe for NADH detection, which would further benefit the field of NADH related disease diagnostics.
authors.affiliation: Med-x Research Institute, Shanghai Jiao Tong University, Shanghai 200240, PR China.
authors.forename: Zonglin
authors.initials: Z
authors.lastname: Li
authors.affiliation: School of Chemistry and Chemical Engineering, State Key Laboratory Metal Matrix Composities, Shanghai Jiao Tong University, Shanghai, 200240, PR China.
authors.forename: Wenqiong
authors.initials: W
authors.lastname: Su
authors.affiliation: Med-x Research Institute, Shanghai Jiao Tong University, Shanghai 200240, PR China.
authors.forename: Shuopeng
authors.initials: S
authors.lastname: Liu
authors.affiliation: Med-x Research Institute, Shanghai Jiao Tong University, Shanghai 200240, PR China. Electronic address: dingxianting@sjtu.edu.cn.
authors.forename: Xianting
authors.initials: X
authors.lastname: Ding
mesh_terms: D000327:Adsorption; D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D004247:DNA / Q000737:chemistry*; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D009243:NAD / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D009243:NAD; D006046:Gold; D006108:Graphite; D004247:DNA
keywords: DNA tetrahedron; Electrochemical; Gold nanoparticles; Graphene; NADH detection