Define about the Cellulose acetate electrophoresis (CAE)?
If the hydroxyl groups in cellulose are reacted with acetic anhydride, cellulose is acetylated to form the raw material for cellulose acetate membranes. The characteristics of the membrane will vary with the extent of acetylation, the pore size and thickness of the membranes etc. All forms have advantages over paper. The material is microporous with pore size from 1 to 5 µm for dry membranes, such pore sizes prevent spreading of the bands or spots so that plasma proteins are finely resolved even at low voltages. Because of the higher resolution, cellulose acetate is used to separate isoenzymes, lipoproteins, haemoglobins and for immuno electrophoresis.
Smaller samples can be examined while maintaining high resolution and the greater sensitivity makes the procedure suitable for screening purposes when many samples can be applied to a single strip and run for a short time, thus facilitating visual comparison. Minimal protein adsorption eliminates trailing and gives an almost white background after washing. Cellulose acetate strip holds little water, so loss by evaporation must be minimized by using buffers of lower ionic strength to reduce the current and the heating effect at a given potential gradient. The migration rate and band width vary inversely with buffer concentration. For best results, fresh buffer should be employed for each run by using just enough buffers to cover the bottom of the tank. Where bubbles are present between compartments, wicks which reach to the bottom of the tank may be used. An advantage of CAE is the speed of separation (20 minutes to 1 hour) and the ability to store the transparent membranes for long periods.