High-speed separation using miniaturized slab gel and high spatial resolution detection by thermal lens microscope

Slab gel electrophoresis is a major tool for size-separation of DNA fragments and proteins. However, conventional slab gel electrophoresis uses a large gel to obtain sufficient separation and it takes several hours to separate, because conventional detectors using radio isotopes and fluorescence are affected by the strongly light-scattering gel and do not have enough spatial resolution to be applied to a miniaturized gel. Thermal lens microscope (TLM), which we have developed, has spatial resolution of micrometer level, and is not easily affected by the scattered light and can maintain high spatial resolution We demonstrate here high-speed separation using a miniaturized eel and successive high spatial resolution detection using TLM. Using a miniaturized gel one-tenth of conventional gel in size, DNA fragments (100 base pair ladder sample) were separated in 5 to 15 minutes, which was about one order of magnitude faster than using a conventional gel, and successfully detected by TLM.