1 4 ml minute the mobile phase can be maintained at a constant or near constant ph e g a ph of about 7 0 7 5 8 0 or 8 5 the column can be maintained at a constant temperature throughout the separation e g using a commercial column heater in some embodiments the column can be maintained at a temperature from about 10 u00b0 c to about 30 u00b0 c e g about 10 u00b0 c 15 u00b0 c 18 u00b0 c 20 u00b0 c 22 u00b0 c 25 u00b0 c 30 u00b0 c oscs separated from a heparin preparation by the methods described herein can be detected by numerous means including e g by ultraviolet absorbance e g at a wavelength of about 215 nm additionally a standard can be used in the methods described herein examples of standards include oscs at a predetermined concentration and or an unfractionated heparin preparation that does not have a detectable level of oscs the oscs standard can be in a solvent in an embodiment the oscs standard can be in a preparation of heparin that does not have a detectable level of oscs sax hplc was used to detect oscs present at various concentrations.