Biochemical Techniques and Instrumentation (1+2)

2.6.3. Plate preparation

TLC plates are prepared by mixing the adsorbent eg. silica gel with a small amount of inert binder such as calcium sulfate or gypsum and water. This mixture is spread as thick slurry on an unreactive carrier sheet, such as glass or thick aluminum foil or plastic. The resultant plate is dried and activated by heating in an oven for 30 min at 110 °C. The thickness of the adsorbent layer is typically around 0.1 – 0.25 mm for analytical purposes and 0.5 – 2.0 mm for preparative purposes. Precoated TLC plates are commercially available with standard particle sizes with improved reproducibility.