Monitoring of low concentrations of glucose in fermentation broth

A highly sensitive glucose sensor, operating in flow-injection analysis (FI A) mode, was developed for the detection of glucose in fermentation broth. The assay system is based upon the post-column reaction of the peroxide for med in the glucose-oxidase-catalysed reaction and subsequent spectrophotome tric detection of the coloured product formed. The sensor system was charac terised and calibrated using standard solutions, and later used for quantif ication of glucose in fermentation media. Two types of enzyme column were u sed: one operated in packed-bed mode and the other in expanded-bed mode. Bo th columns were integrated into a FIA system and were found to give good an alytical results. Glucose concentrations as low as 0.1 mg/l and 5 mg/l coul d be detected in packed- and expanded-bed modes respectively. Glucose conce ntrations were measured during typical fed-batch fermentation conditions in this system, and the results are presented.