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Handbook of Size Exclusion Chromatography and Related ...

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Figure 11 Dependence <strong>of</strong> column performance parameters on SEC column dimensions<br />

<strong>and</strong> pore volume. [1] Traditional analytical SEC column (8 300 mm), [2] short SEC<br />

column (8 50 mm), [3] narrow-bore SEC column (4 250 mm), <strong>and</strong> [4] short wide-bore<br />

SEC column (20 50 mm).<br />

The column with the best overall performance is certainly the conventional<br />

column. This is no surprise since this product has been optimized for highest<br />

performance/price <strong>and</strong> has been in use in many laboratories for years. The<br />

conventional column performs extremely well in all areas studied. The next best<br />

design for polymeric applications is the short wide-bore column. It is quite<br />

obvious that the resolution must be enhanced by using a specially designed<br />

packing with optimized pore architecture. This can also be seen in Fig. 11.<br />

As a general rule the following conclusions can be drawn:<br />

. For least time requirement a short wide-bore column should be used, <strong>and</strong><br />

. For lowest eluent consumption a short <strong>and</strong> thin column is best.<br />

4 HOW CAN HIGH-SPEED SEC COLUMNS BE MADE?<br />

The previous chapter has shown the potential <strong>and</strong> shortcomings <strong>of</strong> various<br />

methods to overcome the time restraints in conventional SEC experiments. In<br />

order to utilize the short wide-bore columns best, new packing materials have to be<br />

designed that overcome the pore access limitations <strong>of</strong> conventional packings.<br />

Conventional analytical columns have been optimized for their typical flow rates<br />

© 2004 by Marcel Dekker, Inc.

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