Impurity evaluation of heparin sodium by anion exchange chromatography
Heparin is a heterogeneous group of straight-chain anionic mucopolysaccharides, called glycosaminoglycans, having anticoagulant properties. Heparin is known to be involved in a number of important biological processes. Heparin and its derivative, low-molecular-weight heparin (LMWH), have been widely used as clinical anticoagulant drugs for decades during surgery and kidney dialysis.
The U.S. Pharmacopia (USP) has revised the monographs for heparin sodium following recent reports of serious reactions and deaths associated with heparin containing an adulterated ingredient. Oversulfated chrondroitin sulfate (OSCS) is the contaminant associated with the adverse clinical events. Stage 2 revisions of the monograph are scheduled to be implemented in August 2009 and official in October 2009. As proposed in the monograph, Waters has developed an ion-exchanged method to separation oversulfated chondroitin sulfate (OSCS) in heparin sodium.
Analysis of oligosaccharides derived from heparin by ion-pair LC/MS
Heparin possesses several biological activities that extend beyond anticoagulation. For example, heparin oligosaccharide structures have been found to play a role in mediating several major diseases including inflammation, Alzheimer's disease, and cancer, making them of great interest in new drug discovery. Despite its medical and biological importance, heparin is relatively uncharacterized in terms of its chemical structures. The limited success in structural characterization is largely attributed to the chemical heterogeneity and the structural complexity of heparin.
Current chromatographic and mass spectrometric techniques have limitations for analyzing heparin and heparin oligomers due to their high polarity, structural diversity, and sulfate lability. A rapid method for the analysis of heparin oligosaccharides was developed using ion-pair reversed-phase UPLC coupled with electrospray quadrupole time-of-flight mass spectrometry (IPRP-UPLC / ESI-QTof MS). The method enables the effective online coupling of IPRP-UPLC to ESI-MS such that the performance characteristics of the UPLC separation and the quality of the MS data are not compromised.