Novel label-free electrochemical strategy for sensitive determination of ten-eleven translocation protein 1

A label-free electrochemical method was developed for sensitive determination of ten-eleven translocation protein 1 (TET1) which can mediate the demethylation of DNA. This strategy is mainly based on MspI-mediated restriction endonuclease reaction. Current response difference of the biosensor before and after cleavage by MspI was dependent on the activity and concentration of TET1. With the aid of Au nanoparticles, this method shows a good linear range from 0.0042 μg μL−1 to 0.0210 μg μL −1 with a correlation coefficient of 0.9350 and a low limit of detection 0.00098 μg μL −1. Finally, this method was used to investigate the effects of n-oxalylglycine (NOG) and taxol on activity of TET1. The results indicated that NOG could inhibit TET1 activity but taxol could not. So this electrochemical biosensor could be applied to TET activity evaluation and inhibitor screening in field of biomedicine and clinical diagnosis.