Identification of single molecular DNA methylation points by microfluidic DNA molecule stretching and quantum dot detection

We report a rapid and simple epigenetic analysis based on microfluidic single DNA molecular methylation detection. We developed a microfluidic device to stretch a single DNA molecule and subsequent detection of a methylated DNA base by quantum dot (QD)-immobilized methyl binding domain (MBD) protein. A QD-MBD complex specifically bound to a methylated base of stretched DNA and was detected by a total internal reflection fluorescence microscope (TIRFM). Our method enables us to detect a number of methylation site and identify the methylated positions simultaneously in the simple and rapid manner compared with the conventional methods.