This Application Note describes a high-speed, high-resolution capillary electrophoresis method of heparin and related impurities using highly concentrated buffer in a 25 µm bubble cell capillary. The method can be used to detect heparin and related impurities in a short time.
This document details an optimized capillary electrophoresis (CE) method for determining impurities in heparin samples, specifically oversulfated chondroitin sulfate (OSCS). The method was developed to improve upon the original USP emergency method by increasing resolution and sensitivity. It utilizes a 25 µm inner diameter bubble cell capillary with highly concentrated lithium phosphate buffers at low pH.
The limit of detection for OSCS is well below 0.1%.
The optimal buffer used in this method is 600 mM lithium phosphate at pH 2.5.
A 25 um inner diameter capillary is required when using such a high buffer concentration.