An electrochemical DNA biosensor based on nitrogen-doped graphene/Au nanoparticles for human multidrug resistance gene detection.
Multidrug resistance (MDR) has become a major obstacle to the adequate treatment of cancer patients; thus, there is an urgent need for exploring new strategies for early diagnosis of MDR in clinic. Here, we report a novel electrochemical biosensor based on nitrogen-doped graphene nanosheets functionalized with Au nanoparticles (N-G/Au) for sensitive and selective DNA detection. The highly conductive nanocomposite layer was characterized by using scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, and cyclic voltammetry. DNA with thiol groups at the 5' end was immobilized on the N-G/Au surface via the strong Au-S bond. Differential pulse voltammetry was applied to monitor the target DNA hybridization event using methylene blue as an electrochemical indicator. Under optimal conditions, the biosensor could detect target DNA down to 3.12×10(-15)M with a linear range from 1.0×10(-14) to 1.0×10(-7)M, showing high sensitivity. Further, the sensing strategy was successfully used for detecting MDR1 DNA in real clinical samples. These results will aid in developing a new portable detection system for MDR that will allow effective diagnosis in the early stages of related cancer.
Key Laboratory of Biorheology Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China.
Mei
M
Chen
Key Laboratory of Biorheology Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China; National Key Laboratory of Fundamental Science of Micro/Nano-Device and System Technology, Chongqing University, Chongqing 400044, China. Electronic address: houcj@cqu.edu.cn.
Changjun
C
Hou
Key Laboratory of Biorheology Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China.
Danqun
D
Huo
Key Laboratory of Biorheology Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China.
Jing
J
Bao
College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China.
Huanbao
H
Fa
National Engineering Research Center of Solid-State Brewing, Luzhou, Sichuan 646000, China.
Caihong
C
Shen
D015374:Biosensing Techniques; D004247:DNA / Q000032:analysis / Q000235:genetics*; D015342:DNA Probes / Q000737:chemistry / Q000235:genetics; D055664:Electrochemical Techniques; D004566:Electrodes; D019450:Genes, MDR; D006046:Gold / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D009584:Nitrogen / Q000737:chemistry*; D009693:Nucleic Acid Hybridization / Q000379:methods; D012680:Sensitivity and Specificity
D015342:DNA Probes; D006046:Gold; D006108:Graphite; D004247:DNA; D009584:Nitrogen
Au nanoparticles; DNA detection; Electrochemical biosensor; Multidrug resistance gene; Nitrogen-doped graphene