Chromatography such as GC, HPLC

A review of chromatographic methods is beyond the scope of this contribution. Both liquid chromatography (LC) and gas chromatography (GC) have been applied in numerous cases to off-line analyses of biotechnological samples but the on-line application has only recently been developed. The scope of chromatographic methods is the separation of the individual constituents of mixtures as they pass through columns filled with suitable stationary phases (Fig. 20). The 

HPLC systems were helpful in monitoring cephalosporin production [174] and p-cresol degradation [392]. Other HPLC systems have been reported to serve for the control of penicillin production, namely via the precursor feed [62, 288],3-chlorobenzoate conversion [375] or naphthalenesulfonic acid reduction [279], as well as amino acids [444,445]. HPLC is also found to be useful when linked to biochemical assays [316]. Mailinger et al. [262] have discussed many important aspects of on-line HPLC systems. 

It is possible after some adaptation and modification to link such apparatuses to bioreactors ( intelligent analytical subsystems ). This trend towards increased automation is not restricted to chromatographic methods (cf. FIA). 

---