A sensitive photoelectrochemical immunoassay of N6-methyladenosine based on dual-signal amplification strategy: Ru doped in SiO2 nanosphere and carboxylated g-C3N4

Publication date: 15 January 2018
Source:Biosensors and Bioelectronics, Volume 99
Author(s): Haiyan Wang, Chunling Qi, Wenhuan He, Minghui Wang, Wenjing Jiang, Huanshun Yin, Shiyun Ai
A novel, simple and sensitive photoelectrochemical (PEC) immunosensing platform was constructed for detecting N⁶-methyladenosine (m⁶A) based on the carboxylated CN and avidin functionalized Ru@SiO2 (ARS) nanocomposite. Herein, the N⁶-methyladenosine-5′-triphosphate (m⁶ATP) was selected as the detection target molecule, m⁶A antibody was used as recognition unit for m⁶A, the carboxylated g-C3N4 (CN) was not only used as the photoactive substance, but the substrate for the m⁶A antibody immobilization, ARS was synthesized and used as signal amplification unit to improve the photocurrent of CN, Phos-tag-biotin was employed as bridge of m⁶ATP and Ru@SiO2 through the specific interaction between phosphate group of m⁶ATP and Phos-tag, biotin and avidin, respectively. Under the optimal condition, the fabricated PEC biosensor showed a linear range of 0.01–10nM and high detection sensitivity with low detection limit of 3.23pM for m⁶ATP. Besides, the developed strategy was also successfully applied to evaluate the content of m⁶A in human serum samples.

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