Immobilized glucose oxidase used to measure glucose in serum.

We report an analytical system in which glucose oxidase immobilized on controlled-pore glass is used. The immobilized glucose oxidase was packed in a column that was part of a continuous-flow system. Oxygen depletion of the buffer was measured with a Clark-type electrode, and the resulting data were stored on tape and then evaluated with a PDP-12 computer. The relative advantages of several measurement approaches are given: (a) an endpoint method for prediluted sample, (b) an endpoint method for discrete, undiluted 9-tl samples, and (C) a maximum reaction rate measurement with discrete, undiluted samples. Catalase and mutarotase interferences were considered and found insignificant under the conditions chosen. The effects of protein, fluoride, and oxalate were determined. The column can be re-used for at least 1000 samples. Useful storage life of the immobilized glucose oxidase preparation, measured at intervals during a year, exceeded one year at room temperature.