Magnetic bead-liposome hybrids enable sensitive and portable detection of DNA methyltransferase activity using personal glucose meter.

DNA methyltransferase (MTase) plays a critical role in maintaining genome methylation patterns, which has a close relationship to cancer and bacterial diseases. This encouraged the need to develop highly sensitive, simple, and robust assays for DNA MTase detection and inhibitor screening. Herein, a simple, sensitive, and specific DNA MTase activity assay was developed based on magnetic beads-liposome hybrids combined with personal glucose meter (PGM) for quantitative detection of DNA MTase and inhibitor screening.

Magnetic nanoparticles-cooperated fluorescence sensor for sensitive and accurate detection of DNA methyltransferase activity coupled with exonuclease III-assisted target recycling.

A fluorescence magnetic biosensor for the DNA methyltransferase activity was developed based on the cooperative amplification by combining the magnetic nanoparticles synergistic exonuclease III (Exo III)-assisted circular exponential amplification and a supramolecular structure ZnPPIX/G-quadruplex. First, a duplex DNA probe, which was constructed by the hybridization of a quadruplex-forming oligomer with a molecular beacon, was assembled on the magnetic nanoparticles (MNPs) as a reporter. A hairpin probe (HP)-containing sequence of GATC was used as the methylation substrate of DNA adenine methyltransferase (DAM).