Handbook of Size Exclusion Chromatography and Related ...

Figure 1 SEC chromatogram of column with 15 cm column length run in THF at a flow
rate of 1.0 mL/min and temperature of 408C. (From Ref. 3.)
2.3 Flow Injection Analysis (FIA)
Another method to cut down on analysis time is to avoid separation altogether and
inject samples directly into detector cells. Unfortunately, this cannot be done in
dilute solutions, because the signals from the solvents must be separated out from
the sample response (Fig. 2).
This method has to be used with expensive molar mass sensitive detectors
(like light scattering and/or viscometry) to obtain a single result from each
detector (Mw and/or IV, respectively). A concentration detector is also needed in
most applications to obtain the concentration of the sample. If only a concentration
detector is used, the only measured parameter is polymer content in a sample,
which can also be determined with various other well-established methods.
The FIA approach requires expensive and well-maintained equipment and will
Figure 2 Flow injection analysis with short column to separate solvent and sample run in
THF at a flow rate of 1.0 mL/min and temperature of 608C. (From Ref. 4.)
© 2004 by Marcel Dekker, Inc.