The present state of studies on attractive and amphiphilic multi-functional methylated β-cyclodextrins and their purity measurements

• Published in: Journal of inclusion phenomena and macrocyclic chemistry Vol. 95; no. 3-4; pp. 285 - 293
• Main Authors: Kimura, Madoka, Honda, Chie, Hamaguchi, Ryohei, Kuroda, Yukihiro, Tanimoto, Toshiko, Terao, Keiji
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.12.2019; Springer Nature B.V
• Subjects: Bombardment; Chemistry; Chemistry and Materials Science; Chromatography; Cosmetics; Crystallography and Scattering Methods; Cyclodextrins; Food Science; High performance liquid chromatography; Inclusion complexes; Ions; Mass spectrometry; Organic Chemistry; Organic compounds; Original Article; Performance enhancement; Refractivity; Scientific imaging; Spectroscopy; Substitutes; Sugar; Methylated β-cyclodextrins; RID; HILIC; MS; HPLC
• ISSN: 1388-3127; 1573-1111
• DOI: 10.1007/s10847-019-00943-5

β-Cyclodextrins (β-CD) are widely used in multiple fields such as medicine, agriculture, alimentation, and cosmetics because their hydrophobic cavity enables the formation of inclusion complexes with various organic compounds to improve their performances. There are three types of methylated β-CDs (M-β-CDs) on the market, prepared by the introduction of methyl groups on various sites: 2,3,6-tri- O -methyl-β-CD (TM-β-CD), 2,6-di- O -methyl-β-CD (DM-β-CD), and randomly methyl-β-CD (RM-β-CD). M-β-CDs are now used in medical as well as non-medical systems due to their significant water solubility compared to β-CD and unique amphiphilic property in water and organic solvents despite the possibility of tissue damage from nephrotoxicity. It is important to investigate the degree of substitution of M-β-CDs by methyl groups for further applications in a wide range of fields. Studies investigating the substitution degree of M-β-CDs have been carried out for many years. The aim of this study is to analyze the tendency of substitution number of methyl group in RM-β-CD, as a simpler analysis method. First, we analyzed RM-β-CD with simple methods such as hydrophilic interaction chromatography (HILIC) using a refractive index detector (RID) that is widely used for the high performance liquid chromatography (HPLC) analysis of sugars. After separation, liquid chromatography/electrospray ionization mass spectrometry and fast atom bombardment mass spectrometry measurements were carried out on each fraction. In addition, TM-β-CD and DM-β-CD were also analyzed by reverse phase-HPLC with ODS column.