Site-specific DNA cleavage of EcoRI endounclease probed by electrochemical analysis using ferrocene capped gold nanoparticles as reporter

An electrochemical method was proposed to study DNA cleavage by EcoRI endonuclease using ferrocene as electrochemical indicator. Ferrocene was not covalently crosslinked to the DNA molecule but co-immobilized on the gold nanoparticles with thiolated target DNA via Au–S bond. EcoRI–DNA interaction was monitored based on the alteration of ferrocene signal before and after digestion with EcoRI. Enzymatic cleavage specificity of EcoRI was investigated, and enzymatic cleavage at DNA-modified electrode was also monitored real-time.