title: A facile and pragmatic electrochemical biosensing strategy for ultrasensitive detection of DNA in real sample based on defective T junction induced transcription amplification.
abstract: A novel and pragmatic electrochemical sensing strategy was developed for ultrasensitive and specific detection of nucleic acids by combining with defective T junction induced transcription amplification (DTITA). The homogeneous recognition and specific binding of target DNA with a pair of designed probes formed a defective T junction, further triggered primer extension reaction and in vitro transcription amplification to produce numerous single-stranded RNA. These RNA products of DTITA could hybridized with the biotinylated detection probes and immobilized capture probes for enzyme-amplified electrochemical detection on the surface of the biosensor. The proposed isothermal DTITA strategy displayed remarkable signal amplification performance and reproducibility. The electrochemical DNA biosensor showed very high sensitivity for target DNA with a low detection limit of 0.4 fM (240 molecules of the synthetic DNA), and can directly detect target pathogenic gene of Group B Streptococci (GBS) from as low as 400 copies of genomic DNA. Moreover, the established biosensor was successfully verified for directly identifying GBS in clinical samples. This proposed strategy presented a simple and pragmatic platform toward ultrasensitive and handy nucleic acids detection, and would become a potential tool for general application in point-of-care setting.
authors.affiliation: The Center for Clinical Molecular Medical detection, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China; Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, PR China.
authors.forename: Rui
authors.initials: R
authors.lastname: Yuan
authors.affiliation: Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, PR China.
authors.forename: Shijia
authors.initials: S
authors.lastname: Ding
authors.affiliation: Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, PR China.
authors.forename: Yurong
authors.initials: Y
authors.lastname: Yan
authors.affiliation: Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, PR China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: The Center for Clinical Molecular Medical detection, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China.
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: The Center for Clinical Molecular Medical detection, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China. Electronic address: chengwei@cqmu.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Cheng
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D004269:DNA, Bacterial / Q000032:analysis* / Q000235:genetics; D004867:Equipment Design; D019544:Equipment Failure Analysis; D021141:Nucleic Acid Amplification Techniques / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013291:Streptococcus / Q000235:genetics* / Q000302:isolation & purification*
chemical_list: D004269:DNA, Bacterial
keywords: Electrochemical DNA biosensor; Group B Streptococci; Signal amplification; Transcription amplification