Evaluation of a Dye Binding Method for Determining the Solution Concentration of Low Molecular Weight Heparins.

Low Molecular Weight Heparins are carbohydrate-based therapeutics with anticoagulant activities. Common brands include: Lovenox, Fragmin and Arixtra, which are currently used to treat Deep Vein Thromobosis. Unlike protein or peptide-based drugs, easy test methods for measuring the concentration of carbohydrates in solution are not available. In this report, we extend the use of commercially available dye-binding reagents and protocol (Biocolor Ltd, Ireland) for rapidly measuring the solution concentration of LMWHs. The assay was evaluated according to typical validation parameters: Linearity, Accuracy, Precision (Reproducibility and Intermediate), Solution Stability and Specificity. The assay is also capable of monitoring LMWH “stability” as changes in the dye binding response appears associated with changes in Anti-fXa and anti-fIIa activity, Molecular Weight and Free Sulfate levels. The assay was also used to measure the concentration of two Products, Lovenox (99.6% of claim) and Fragmin (94% of claim), from pre-filled syringes.