| Automated multiple development(AMD) is an advanced TLC technique. It has some characteristics as follows: development is always in the same direction and with each development the migration distance is increased and the polarity of the solvent is reduced; after each development the solvent is removed, and the plate is dried before redevelopment in the same direction.At present, the commercial instruments are too expensive to be widely accepted, besides, it wastes too much solvent. A new version AMD instrument made by us is described in this paper, the differences are:1. A self-made horizontal sandwich chamber is used as the developmentchamber.2. The most expensive part motor driven valve is omitted in our device, which makes the cost of the instrument very low.3. A micro air pump (compressor) is used to push mobile phase to the chamber. So vacuum pump and external supply of compressed air, which commercial instrument require, are not required. |
