DNA methylation detection with end-to-end nanorod assembly-enhanced surface plasmon resonance.

The Au nanorod (AuNR) assembly-enhanced surface plasmon resonance (SPR) system coupling with polymerization and nicking reactions was developed for amplified detection of DNA methylation and adenine methylation (Dam) methyltransferase (MTase) activity assay. The biosensor showed a good linear relationship between the SPR angle shift and the Dam MTase concentration over a range from 0.5 to 120 U mL(-1), with a detection limit of 0.2 U mL(-1). This study provided a sensitive platform to screen inhibitors for Dam MTase with great potential to be further applied in early clinical diagnosis.