Thin-layer chromatography of cyclodextrins and some other sugars using micro-chromatoplates

The a- (I) and b-cyclodextrins (II) were sepd. on micro-chromatoplates (Peifer, CA 57, 1511g). Adsorbents were Kiesel-G \"Merck\" (A) and Alusil layers (B) (25 g. each A and Al2O3-G \"Merck\" in 2:1 CHCl3-MeOH). The best solvents were 6:3:1:2:4 BuOH-HOAc-H2O-C5H5N-HCONMe2 (C) and 6:3:1 BuOH-HOAc-H2O (D). The indicator spray was a mixt. of 10 ml. H2SO4, 20 ml. H2O, and 3 g. K2Cr2O7. The Rf values of I and II, resp., on A with C are 0.0 and 0.5; similar values are found on B with C, but the spots are less sharp. I, II, glucose, and maltose were sepd. on A by development first with solvent D, allowing D to reach the end of the adsorbent, letting stand 4 min., vaporization of D, then development with solvent C.