ON-LINE DETERMINATION OF GLUCOSE AND LACTATE CONCENTRATIONS IN ANIMAL CELL CULTURE BASED ON FIBRE OPTIC DETECTION OF OXYGEN IN FLOW-INJECTION ANALYSIS

Abstract

A flow-injection analysis (FIA) system for on-line monitoring of glucoseandlactate concentrations in animal cell cultures based onfibre optic detection of oxygen consumption using immobilized glucose oxidase (GOD) and lactate oxidase (LOD) is described. The consumption of oxygen was determined via dynamic quenchingof the fluorescenceof an indicator by molecular oxygen. GOD and LODwere immobilized on controlled pore glass (CPG) in enzyme reactors which weredirectly linked to a specially designed fibre optic flow through cell covering the oxygenoptrode. The system is linear for 0 - 30 mM glucose, with a r.s.d. of 5% at 30 mM (5 measurements) and for 0 - 30 mM lactate, with ar.s.d. of 5 % at 30 mM (5 measurements). The enzyme reactors used were stable for more than 4 weeks in continuous operation, and it was possible to analyse up to 20 samples per hour. The system has been successfully applied to on-line monitoring of glucose and lactate concentration of an animalcell culture, designedfor the production of recombinant human antithrombine Ill (AT-III).