title: High-resolution separation of homogeneous chitooligomers series from 2-mers to 7-mers by ion-exchange chromatography.
abstract: Highly purified chitooligomers with single degree of polymerization are of significance for studying bioactivity of chitooligomers. However, there are few reports on high-resolution preparative separation of chitooligomers, especially for those oligomers with degree of polymerization higher than 4. This study developed a high-resolution chromatography for the preparative separation of a pure fully deacetylated chitooligomer series. A glucosamine oligomer mixture with low degree of polymerization was prepared by acid hydrolysis of a highly deacetylated chitosan. Then, six fractions were separated from the prepared oligomer mixture by ion-exchange chromatography and analyzed by HPLC and ESI/MS, which primarily contained glucosamine dimers, trimers, tetramers, pentamers, hexamers, and heptamers, respectively, with chromatographic purities over 98% for dimers to hexamers and a purity of 93% for heptamers. The yields of a single round of separation were 75, 60, 60, 55, 35, and 20 mg for glucosamine dimers, trimers, tetramers, pentamers, hexamers, and heptamers, respectively. Furthermore, a chromatographic separation model for GlcN homomers was established. The capacity factor (k) of glucosamine oligomers and their degrees of polymerization (DPs) exhibited a good correlation, lnk = 0.786 + 0.846 lnDP, (R(2) = 0.997). Based on this equation, glucosamine octamers are expected to be separated by this system.
authors: Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
authors: Kecheng
authors: K
authors: Li
authors: Song
authors: S
authors: Liu
authors: Ronge
authors: R
authors: Xing
authors: Huahua
authors: H
authors: Yu
authors: Yukun
authors: Y
authors: Qin
authors: Rongfeng
authors: R
authors: Li
authors: Pengcheng
authors: P
authors: Li
mesh_terms: D048271:Chitosan / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D009844:Oligosaccharides / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D009844:Oligosaccharides; D048271:Chitosan