Functionalized graphene oxide as a nanocarrier in a multienzyme labeling amplification strategy for ultrasensitive electrochemical immunoassay of phosphorylated p53 (S392).

摘要: P53 phosphorylation plays an important role in many biological processes and might be used as a potential biomarker clinical diagnoses. We report new electrochemical immunosensor for ultrasensitive detection of phosphorylated p53 at Ser392 (phospho-p53392) based on graphene oxide (GO) nanocarrier multienzyme amplification strategy. Greatly enhanced sensitivity was achieved by using the bioconjugates featuring horseradish peroxidase (HRP) p53392 signal antibody (p53392Ab2) linked to functionalized GO (HRP−p53392Ab2−GO) high ratio HRP/p53392Ab2. After sandwich immunoreaction, HRP−p53392Ab2−GO captured onto electrode surface produced amplified electrocatalytic response reduction enzymatically oxidized thionine presence hydrogen peroxide. The increase current proportional phospho-p53392 concentration range 0.02−2 nM with limit 0.01 nM, which 10-fold lower than that traditional elec...