Short communication: Effect of Ca on the H NMR chemical shift of the methyl signal of oversulphated chondroitin sulphate, a contaminant in heparin

The chemical shift of the methyl signal of oversulphated chondroitin sulphate (OSCS) is dependent on the type and concentration of the counterion. When OSCS is present as a contaminant in heparin sodium, the reported methyl 1H chemical shift is 2.15 plus or minus 0.02 ppm. In this report, a value of...

Full description

Saved in:
Bibliographic Details
Published in:Journal of pharmaceutical and biomedical analysis 2009-04, Vol.49 (3), p.816-819
Main Authors: McEwen, Ian, Rundlof, Torgny, Ek, Marianne, Hakkarainen, Birgit, Carlin, Gunnar, Arvidsson, Torbjorn
Format: Article
Language:English
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The chemical shift of the methyl signal of oversulphated chondroitin sulphate (OSCS) is dependent on the type and concentration of the counterion. When OSCS is present as a contaminant in heparin sodium, the reported methyl 1H chemical shift is 2.15 plus or minus 0.02 ppm. In this report, a value of 2.18 plus or minus 0.01 ppm is reported for the OSCS in the presence of Ca2+. The chemical shift of the methyl signal of pure OSCS varies linearly from 2.13 ppm to 2.18 ppm with increasing amounts of Ca2+, until reaching the saturation point of four Ca2+ ions per OSCS disaccharide unit, which contains four sulphate groups (a 1:1 ratio between sulphate groups and Ca2+). This Ca2+ effect can be used for OSCS identification as well as to facilitate quantification.
ISSN:0731-7085
DOI:10.1016/j.jpba.2008.12.012