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Handbook of Size Exclusion Chromatography and Related ...

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Figure 17 Accuracy <strong>and</strong> precision <strong>of</strong> fast SEC analysis in water tested with reference<br />

dextran samples (PSS Suprema HighSpeed 100 þ 1000 columns).<br />

Aqueous samples can also be analyzed by HighSpeed SEC methods.<br />

Polyacrylic acids, pullulans, <strong>and</strong> dextrans have been investigated. The accuracy<br />

<strong>and</strong>reproducibility<strong>of</strong>dextranresultstestedwithvariousdextransamples(T-series<br />

by Pharmacia) havebeen evaluated (Fig. 17). Result precision has been similar to<br />

conventionalanalyses,whilegoodaccuracyhasbeenreportedforMw <strong>and</strong>Mp (14).<br />

Mn results have been low,because <strong>of</strong> nonideal flow pr<strong>of</strong>iles in water at ambient<br />

temperature.Owingtothehighviscosity<strong>of</strong>water,theuse<strong>of</strong>elevatedtemperatures<br />

is recommended for increased resolution.<br />

Kilz <strong>and</strong> Pasch used HighSpeed columns to speed up analysis time <strong>of</strong><br />

two-dimensional chromatography experiments (17). They were able to cut down<br />

2D run times from 10 hours to about 1hour, while maintaining the efficiency <strong>of</strong><br />

the 2D separation as shown for aseparation <strong>of</strong> polystyrene <strong>and</strong> polybutadiene<br />

st<strong>and</strong>ards<strong>of</strong>differentmolarmass(Fig.18).About60transferinjectionshavebeen<br />

made in this experiment.<br />

4.4 Can HighSpeed Columns also be used for<br />

FIA Applications?<br />

FIA (or FIPAas it is called by Viscotek) does not rely on any separation <strong>of</strong> the<br />

sample,butcanbeconsideredasasamplepreparation<strong>and</strong>introductionmethodin<br />

© 2004 by Marcel Dekker, Inc.

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