Heterogeneity of Heparin

Interactions among Heparin, Cold-Insoluble Globulin, and Fibrinogen in Formation of the Heparin-Precipitable Fraction of Plasma

“…Anticoagulant activity of heparin in the heparinprecipitable fraction. It is well known that heparin preparations consist of a group of closely related polydisperse glycosaminoglycans (36)(37)(38)(39). Recent studies by Lam et al.…”

The Determination of Molecular Weight Distributions on Heparin Samples

“…It is an established fact that heparin is a heterogeneous mixture composed of sulfated aminoglycans of varying chain lengths. 4,14 Published results 1,7 have shown a molecular weight dependence for heparin in its inhibition of thrombin and factor Xa with the antifactor Xa activity being more pronounced in the low molecular weight polymers. Lane et al 8 have reported that molecular size has an effect on heparin absorption depending on the route of administration.…”

Simple metachromatic assay methods for heparin and protamine

“…The heparin-dye complexes are however very sparingly soluble; this is an advantage when the dyes are used as stains in histology and electrophoresis, but has led to considerable complications if quantitative estimations in solution are required (Walton & Ricketts, 1954). For some years we have used a simple procedure which ignores rather than circumvents the supposed hazard of precipitation, but which nevertheless is reproducible enough to have become our standard 'chemical' means of estimating heparin concentrations (not its anticoagulant activity) whenever it is applicable.…”

“…Over many years methods have been described for estimating heparin and other acidic mucopolysaccharides by their metachromatic reaction with basic dyes such as toluidine blue (Walton & Ricketts, 1954) and azure A (Jaques & Wollin, 1967). The heparin-dye complexes are however very sparingly soluble; this is an advantage when the dyes are used as stains in histology and electrophoresis, but has led to considerable complications if quantitative estimations in solution are required (Walton & Ricketts, 1954).…”