| Detection of the DNA of Mycobacterium tuberculosis(MTB)is an important way of diagnosis of tuberculosis.Traditional methods of detection of the DNA mainly includes PCR,LAMP,etc.But they all have some limitations,still can not meet the rapid and accurate detection of Mycobacterium tuberculosis.Electrochemical DNA biosensor as a new type of nucleic acid detection means,with excellent selectivity,high sensitivity,portability and low cost characteristics,has a broad experimental and clinical application prospects.In order to further investigate the potential of electrochemical biosensors for detection of Mycobacterium tuberculosis,a biosensor based on tuberculosis-specific DNA fragments was developed.Our study can be divided into two sections:Electrochemical DNA biosensor constribution:This article describes the construction of a sandwich-type of DNA biosensor for detecting a specific DNA sequence of Mycobacterium tuberculosis.A polyaniline-reduced graphene oxide(PANI-rGO)composite with favorable electrochemical activity was used as a redox nanoprobe forthe generation of the voltammetric signal.The nanocomposite was decorated with gold nanoparticles(Au NPs)onto which the signal probe was immobilized to form the tracer label.After hybridization between target DNA and tracer label,the voltammetric signal resulting from the polyaniline-reduced graphene oxide(PANI-rGO)redox probe can be apparently observed.The biosensor can detect the specific IS6110 DNA sequence of MTB in the 0.1 pM to 10 nM concentration range,and the detection limit is as low as 50 fM(at an S / N ratio of 3).This assay provides a versatile and powerful tool for ultrasensitive detection of MTB.Analysis of the clincal samples:It was applied to the determination of denatured PCR products in clinical samples such as sputum,and the results agreed with those obtained by gel electrophoresis.It has proven that this biosensor may hold a great deal of potential for the reliable clinical diagnosis. |
PDF Full Text Request