Application of a computer-controlled flow analyser to the determination of glucose and to the study of β -galactosidase activity

Glucose was determined using an automated flow analyser and a commercial reagent preparation based on the glucose oxidaseperoxidase reaction. The coupling system for the hydrogen peroxide liberated consisted of 4-aminophenazone and 2,4-dichlorophenol. The analyser demonstrated linearity of>0.9997 for five consecutive sets of standards. The average RSD for individual standards is 0.76%, and a sample throughput rate of >80 h(-1) was achieved. The study of β-galactosidase, using a novel substrate, was carried out in a simple single-line manifold. The enzyme-substrate reaction mixture was injected into a pH 10 buffer carrier to stop the reaction, and at the same time, propel the reaction zone to the flow cell. K(m) and V(max) values were calculated.