Analysis of charged cyclomalto-oligosaccharides (cyclodextrin) derivatives by ion-spray, matrix-assisted laser-desorption/ionization time-of-flight and fast-atom bombardment mass spectrometry, and by capillary electrophoresis

The use of electrospray-ionization mass spectrometry (ESIMS), matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDITOFMS), and fast-atom bombardment mass spectrometry (FABMS) for the rapid determination of molecular weight, degree of substitution (ds), and purity is demonstrated for charged derivatives of cyclomalto-heptaose (βCD) and -octaose (γCD). The access to anionic sulfoalkyl ethers (alkyl: ethyl, n-propyl, and n-butyl) and to βCD-2-hydroxy-3-trimethylammoniumpropyl ether chlorides (HTAP-βCD) leads only to mixtures of products, the compositions of which can be determined directly from ESI and MALDITOF mass spectra. All charged derivatives consist of a mixture of unreacted and higher substituted compounds. The substitution patterns obtained by MS are in good agreement with the results of experiments on the separation of βCD-sulfoalkyl ethers by capillary electrophoresis (CE).