A sandwiched electroanalysis method for probing Anthrax DNAs based on glucose-induced gold growth and catalytic coupling of tyramine using gold-mineralized glucose oxidase

• Published in: Sensors and actuators. B, Chemical Chemical, 2018-05, Vol.261, p.441-450
• Main Authors: Wang, Hua, Zhang, Liyan, Jiang, Yao, Chen, Lijun, Duan, Zhiqiang, Lv, Xiaoxia, Zhu, Shuyun
• Format: Article
• Language: English
• Subjects: Anthrax; Catalysis; Deoxyribonucleic acid; DNA; DNA detection; Double catalysis activities; Electrolytic analysis; Glucose; Glucose oxidase; Glucose-triggered gold growth; Gold; Gold nanoparticles; Magnetic separation; Mineralization; Nanoparticles; Peroxidase; Proteins; Tyramine-labelled
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2018.01.171

Gold-doped glucoseoxidase (GOx) was fabricated via biomineralization for the electroanalysis of Anthrax DNAs by the catalytic linking of tyramine-labelled DNA probes and gold growth. [Display omitted] •Glucose oxidase (GOx) is remolded by in-site gold biomineralization yielding GOx-Gold.•GOx-Gold shows the double catalysis activities of GOx and peroxidase-like gold catalysis.•GOx-Gold and tyramine linker are employed separately as the labels of DNA probes.•The catalytic linking of tyramine-labelled DNA probes and gold growth is involved.•The electroanalysis strategy enables the DNA detection and base-mutation discrimination. Gold nanoparticles was doped into the protein matrix of glucose oxidase (GOx) by the in-site biomineralization route, yielding the GOx with mineralized gold (GOx-Gold) showing the double catalysis activities of GOx and peroxidase-like gold catalysis. A magnetic separation-based detection method was thus tailored for the sandwiched electroanalysis of Anthrax DNAs using GOx-Gold and tyramine linker as the probe labels. After the DNA hybridization reactions, the tyramine-mediated linking of DNA capture and detection probes was conducted through gold-catalytic oxidization of tyramines labelled at the probe terminuses, followed by the glucose-triggered gold growth catalyzed by GOx. Highly amplified electrochemical output of gold signals was thus achieved toward the ultrasensitive detection of DNAs in blood, with the detection limit down to ∼0.10 fM. Also, the discrimination of DNAs with single-base mutation could be expected. Importantly, such a biomimic gold mineralization route can be tailored for remolding various enzymes with improved intrinsic catalysis and electrocatalysis, thus promising the wide applications in the catalysis, biosensing, and biomedical fields.