Abstract: A new thin layer plate, the RP-C18 sintered plate, is described. The electroosmotic flow can be produced without any buffer salts by the carefully controlled bonding degree. It is very convenient and saves a lot of time. Some new development modes and skills can be derived. Based on the firmness of the new plate the operator can brush the mobile phase on the plate directly, which is very simple and fast for wetting the plate and saves much reagent. If the plate becomes dry during the process of planar electrochromatography, the operator can re-wet the plate on the local and then develop it again. Such operation can be repeated many times until the spots are separated completely, so it is called multiple-electro-development. The buffer salt in the mobile phase is abolished, which makes the process of multiple-electro-development possible. As the bonding degree descends, the effect of the plate is not as good as before, but the total separation efficiency and the potential increase due to the multiple-electro-development.

Key words: multiple-electro-development , RP-C18 sintered plate, planar electrochromatography (PEC)