Posters
« Back
The use of multi detection GPC to determine absolute molecular and structural information about low molecular weight Heparins
EP22722
Poster Title: The use of multi detection GPC to determine absolute molecular and structural information about low molecular weight Heparins
Submitted on 19 Feb 2015
Author(s): Paul Clarke, Stephen Ball, John Stenson
Affiliations: Malvern Instruments Ltd
This poster was presented at SCM-7
Poster Views: 1,772
View poster »


Poster Information
Abstract: Low Molecular Weight Heparin (LMWH) is an important and widely prescribed pharmaceutical anticoagulant. This material is derived from Unfractionated Heparin (UFH) which itself is sourced from the mucosal tissue of porcine intestine. Unlike proteins that are biosynthesised through a template driven assembly process, heparins are actively remodelled though a series of enzymatic reactions. Due to this UFH is a complex heterogeneous mixture of polysaccharide molecules, varying in both sequence and number. UFH can have a wide ranging polydispersity with molecular weights ranging from 5,000 Da to 40,000 Da.

LMWH are derived from UFH by fractionation or depolymerisation with different methods being used depending on the manufacturer. These LMWHs have an average Mw of less than 8,000 Da and have a more predictable effect when used medicinally as an anticoagulant.

The macromolecular characterization of these materials is an extremely important process of which molecular weight and polydispersity are a part. In addition, with the recent report of the production of synthetic Heparins [1], it is important to be able to characterize structural differences as well any changes in MW between samples.

The current methods outlined by the European Pharmacopoeia and United States Pharmacopeia for the analysis of LMWH use Gel Permeation Chromatography (GPC) with column calibration. In these methods the retention volume of a LMWH sample is compared to that of a broad heparin standard. This provides only the relative molecular weight and polydispersity of the sample. In comparison, triple detection GPC incorporates refractive index (RI), static light scattering (SLS) and intrinsic viscosity (IV) detectors. The use of these advanced triple detection techniques allows the calculation of the absolute MW of the sample, size, polydispersity and structural information independent of any standards. Triple detections GPC allows any molecular and structural differences between different LMWH’s to be detected.

In this work three commercially available LMWH’s (Enoxaparin, Tinzaparin and Dalteparin) are measured by triple-detection GPC and any differences identified. In addition, structural comparisons will be made with a commercially available low MW Pentosan Sulfate. This work will demonstrate the advantages of using triple-detection GPC when making comparisons of Low MW materials.
Summary: In this work three commercially available Low Molecular Weight Heparin samples (Enoxaparin, Tinzaparin and Dalteparin) are measured by triple-detection GPC and any differences identified. In addition, structural comparisons will be made with a commercially available low MW Pentosan Sulfate. This work will demonstrate the advantages of using triple-detection GPC when making comparisons of low MW materials.References: Xu Y et. al. Homogeneous low-molecular-weight heparins with reversible anticoagulant activity.
Nat chem Biol. 2014 Apr;10(4):248-50
Report abuse »
Questions
Ask the author a question about this poster.
Ask a Question »

Creative Commons