The use of ultrafiltration and column liquid chromatography for on-line fermentation monitoring

The applicability of ultrafiltration and column liquid chromatography for the on-line and automated monitoring of small organic compounds during fermentation processes is reviewed. The influence of the construction of the filtration device, the properties of the membrane, the type of sample and the filtration mode on the sampling efficiency is discussed. In addition, different approaches for determining key components in fermentation samples, including the possibilities to increase the sensitivity and/or selectivity of the analytical procedure, are addressed. To illustrate the usefulness of employing online systems, the monitoring of a number of quite different fermentation processes is shown.