This study shows that HPLC-LALLS (high performance liquid chromatography with a light-scattering detector) is a convenient and reliable method for the characterization of standard heparin samples, provided that polyelectrolyte artefacts are suppressed by a suitable dialysis procedure. The method has been succesfully applied to the assessment of calibrated relations like the Mark-Houwink relation and the calibration curve of gel permeation chromatography. Furthermore, this study confirms that gel permeation chromatography for heparins cannot be calibrated with dextranes or polyethyleneglycols, but in addition to this well known fact it is shown that even the universal (hydrodynamic volume) calibration procedure does not work. Moreover, in addition to the familiar conclusion that heparins should be calibrated with heparins, it is shown that calibrated relations are valid only when the calibration has been made with heparin samples of the same origin (i.e. same tissue source, same animal source, and same purification scheme).