The use of circular dichroism as a simple heparin-screening strategy

Heparin, a heterogeneous polysaccharide, is used extensively as an anticoagulant. Recently, however, tainted heparin was associated with acute reactions that lead to numerous deaths. Extensive investigations ultimately showed oversulfated chondroitin sulfate, a semi-synthetic polysaccharide, to be present in the contaminated samples. These events highlighted the need for new, convenient heparin-screening methods capable of rapidly determining sample purity. In this work, we report the use of circular dichroism spectroscopy to analyze heparin samples for the presence of heparin-like adulterants (e.g., chondroitin sulfate A, dermatan sulfate, and oversulfated chondroitin sulfate) in a simple and straightforward manner. This strategy exploits the subtle differences in the optical properties of each polymer; these differences result from structural dissimilarities. To the best of our knowledge, the findings presented here are the first report of heparin purity screening using traditional spectropolarimetry techniques.