PURIFICATION AND ANALYSIS OF PARTIALLY ALKYLATED CYCLODEXTRINS BY LIQUID AND GAS-CHROMATOGRAPHY

Complex mixtures of partially alkylated cyclodextrins can be analyzed by both HPLC and high temperature capillary GC. Because of the limited efficiency of LC, suitable analytical and preparative separations can be achieved only with systems of carefully optimized selectivity. Usi ng LC it has been possible to isolate and purify single cyclodextrin s pecies from very complex mixtures of components which contain unreacte d hydroxyl groups in addition to the alkoxy groups. Analysis of the re action mixtures and of fractions taken from LC separations can be perf ormed with advantage by high resolution capillary GC at high temperatu res between 300 and 400-degrees-C. The thermal stability of partially alkylated cyclodextrins in high temperature GC is considerably increas ed by trimethylsilylation of the free hydroxyl groups. Fast atom bomba rdment mass spectrometry and proton NMR were used to identity species isolated from the preparative LC separations.