Abstract: Serum (80 µL) was injected into a reagent stream (5 mL min-1) of phosphate buffer (pH 7) containing 0.1% of Tween 20 and 0.5 µM-Pd(II) - coproporphyrin I complex and passed through a column (7 cm x 5 mm) of glucose oxidase immobilized on glass beads. Detection was at 650 to 750 nm (excitation was at 350 to 550 nm). The sample throughput was 20 h-1. The calibration graph was rectilinear from 2 to 300 mM glucose and the coefficient of variation were 3% (n = 5).