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Handbook of Size Exclusion Chromatography and Related ...

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Table 3 Summary <strong>of</strong> Column Performance Criteria with SEC Columns <strong>of</strong> Different<br />

Dimensions<br />

Column design Resolution<br />

Parameter<br />

Plate<br />

count Symmetry<br />

MMD<br />

range<br />

Solvent peak<br />

separation<br />

Analytical J J J J J<br />

High flow analytical L K L J K<br />

Short L K L J K<br />

Narrow-bore L L L J K<br />

Short wide-bore K J J J K<br />

Performance criteria are met well (J), adequately (K), or poorly (L).<br />

short <strong>and</strong> narrow-bore columns. These are, unfortunately,the same columns that<br />

separatethefastest.Thosecolumnswithhighporevolume(seechromatograms[1]<br />

<strong>and</strong> [4] in Fig. 9) shows much better resolution. This figure underlines the<br />

importance <strong>of</strong> pore volume for optimum SEC separations.<br />

Figure 9 Comparison <strong>of</strong> chromatograms <strong>of</strong> SEC columns with different dimensions<br />

tested with identical polystyrene st<strong>and</strong>ards in THF shows the required run time, pore<br />

volume, <strong>and</strong> efficiency (all run at equal volume flow rate <strong>of</strong> 1.0 mL/min). [1] Traditional<br />

analytical SEC column (8 300 mm), [2] short SEC column (8 50 mm), [3] narrowbore<br />

SEC column (4 250 mm), <strong>and</strong> [4] short wide-bore SEC column (20 50 mm).<br />

© 2004 by Marcel Dekker, Inc.

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