title: Enzyme catalytic amplification of miRNA-155 detection with graphene quantum dot-based electrochemical biosensor.
abstract: A specific and sensitive method was developed for quantitative detection of miRNA by integrating horseradish peroxidase (HRP)-assisted catalytic reaction with a simple electrochemical RNA biosensor. The electrochemical biosensor was constructed by a double-stranded DNA structure. The structure was formed by the hybridization of thiol-tethered oligodeoxynucleotide probes (capture DNA), assembled on the gold electrode surface, with target DNA and aminated indicator probe (NH2-DNA). After the construction of the double-stranded DNA structure, the activated carboxyl groups of graphene quantum dots (GQDs) assembled on NH2-DNA. GQDs were used as a new platform for HRP immobilization through noncovalent assembly. HRP modified biosensor can effectively catalyze the hydrogen peroxide (H2O2)-mediated oxidation of 3,3',5,5'-tetramethylbenzidine (TMB), accompanied by a change from colorless to blue in solution color and an increased electrochemical current signal. Due to GQDs and enzyme catalysis, the proposed biosensor could sensitively detect miRNA-155 from 1 fM to 100 pM with a detection limit of 0.14 fM. High performance of the biosensor is attributed to the large surface-to-volume ratio, excellent compatibility of GQDs. For these advantages, the proposed method holds great potential for analysis of other interesting tumor makers.
authors.affiliation: Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules & College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, PR China.
authors.forename: Tianxing
authors.initials: T
authors.lastname: Hu
authors.affiliation: Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules & College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, PR China.
authors.forename: Le
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules & College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, PR China. Electronic address: wenwei@hubu.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Wen
authors.affiliation: Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules & College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, PR China.
authors.forename: Xiuhua
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules & College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, PR China. Electronic address: wangsf@hubu.edu.cn.
authors.forename: Shengfu
authors.initials: S
authors.lastname: Wang
mesh_terms: D001483:Base Sequence; D015374:Biosensing Techniques / Q000295:instrumentation*; D002384:Catalysis; D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite; D006735:Horseradish Peroxidase / Q000737:chemistry*; D035683:MicroRNAs / Q000032:analysis* / Q000235:genetics*; D008969:Molecular Sequence Data; D045663:Quantum Dots; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: C524942:MIRN155 microRNA, human; D035683:MicroRNAs; D006108:Graphite; D006735:Horseradish Peroxidase
keywords: Electrochemical biosensor; Graphene quantum dots; Horseradish peroxidase; miRNA-155