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Two types of new anion-exchange stationary phases were readily prepared by the reaction of porous particles of chloromethylated styrene–divinylbenzene copolymer with various amines. The stationary phases Mn, where n is the length of alkyl chain, were obtained by the reaction with N,N-dimethylalkylamines. The reaction with N,N,N′,N′-tetramethyldiaminoalkanes also afforded the stationary phases Dn with a terminal functional group, where n is the length of methylene bridge. The HPLC separations of monosaccharides, disaccharides and oligosaccharides were successfully performed on these stationary phases using electrochemical detection with a Ni–Ti alloy working electrode in alkaline eluents. The effects of chemical structures of stationary phases on the separation of carbohydrates are described.

Seven chiral stationary phases (CSPS) were prepared by bonding axially dissymmetric 2′-substituted-1,1′- binaphthyl-2-carboxylic acids to aminoalkylsilanized silica gels through an amide linkage, and the effect of the 2′-substituents (CN, COOH, CONH 2 , CONHEt, CONEt 2 and OCH 3 ) was investigated for the high-performance liquid chromatographic (HPLC) separation of enantiomers. Among these CSPS, that which had a 2′-carboxyl substituent showed the best performance and efficiently discriminated several enantiomeric amino acids, amines and alcohols as their 3,5-dinitrophenyl derivatives, and biaryls bearing 2,2′-polar substituents, by normal-phase HPLC. Stereoselective π-donor-acceptor interaction and dipole stacking interaction between the CSPs and the analytes seem to play a critical role in the enantioseparation.

We describe the preparation and effectiveness of novel chiral stationary phases involving two different stereogenic centres, axially chiral 1,1'-binaphthalene-2,2'-dicarboxylic acid coupled with chiral 1-phenylethylamine