<p>This document establishes a valid method for separation of chemically heterogeneous polyethylene oxide (PEO) mixtures and for the determination the number and content of the chemically heterogeneous species in the overall sample.</p>
<p>The method presented in this document serves as a technical guideline and enables laboratories to learn the principle of "critical chromatography" on a validated system.</p>
<p>This method presented in this document with its stated system parameters is not applicable for other polymer classes, due to the diversity of the interactions between the polymer/mobile phase/stationary phase and the number of separation systems that are therefore available.</p>
<p>The evaluation of the interlaboratory testing has shown that many error sources relate to the technique of liquid chromatography in general. Possible error sources are described in Annex A.</p>
<p>Details on the evaluation of the interlaboratory testing are given in Annex B.</p>
<p>Elugrams of the participants (excerpts) are given in Annex C.</p>
<p>Investigations of the long-term stability of the test mixture are given in Annex D.</p>
Registration number (WIID)
77489
Scope
<p>This document establishes a valid method for separation of chemically heterogeneous polyethylene oxide (PEO) mixtures and for the determination the number and content of the chemically heterogeneous species in the overall sample.</p>
<p>The method presented in this document serves as a technical guideline and enables laboratories to learn the principle of "critical chromatography" on a validated system.</p>
<p>This method presented in this document with its stated system parameters is not applicable for other polymer classes, due to the diversity of the interactions between the polymer/mobile phase/stationary phase and the number of separation systems that are therefore available.</p>
<p>The evaluation of the interlaboratory testing has shown that many error sources relate to the technique of liquid chromatography in general. Possible error sources are described in Annex A.</p>
<p>Details on the evaluation of the interlaboratory testing are given in Annex B.</p>
<p>Elugrams of the participants (excerpts) are given in Annex C.</p>
<p>Investigations of the long-term stability of the test mixture are given in Annex D.</p>
