Comparative Evaluation of Precoated Silica Gel Plates for Preparative Layer Chromatography

Five commercial preparative layer chromatography (PLC) plates precoated with silica gel layers 1 mm thick were compared on the basis of theoretical plate number (N) and resolution (R) by developing a test dye mixture with the same mobile phase over a constant distance with dye loadings of 1.0–5.0 μg per zone. It was found that the best performance, on the basis of N and R data, was obtained from the new Mallinckrodt– Baker layer with 4.5–5.5-μm spherical particles. With one exception the efficiency and resolution of the other layers correlated with their particle size.