which Thin-Layer Chromatography plate give he best separation; aluminium,plastic or glass plate?

Answer 1

The separation of samples and/or standards is a function of the Stationary phase and the Mobile phase, not the plate material.

The material that the plate is made from has no influence on the separation of the samples unless a strong acid or alkali is part of the system (which will react with the Aluminum).

Plastic and glass are very similar in TLC properties with glass being more expensive.

Glass plates tend to hold up better with less material flaking off.