Flow-injection spectrophotometric determination of glucose in blood plasma with bindschedler's green leuco base as color reagent

The hydrogen peroxide produces in the oxidation of glucos in an immobilized glucose oxidase reactor is determined by using Bindschedler's green (leuco base) as color reagent with iron(II) as catalyst; the increase in the absorbance at 725 nm is measured. For 100-μl samples, calibration was almost linear in the range 0–2.5 mg l−1 glucose; the relative standard deviation for 1 mg l−1 glucose was 0.6% (n=10) and the detection limit (S/N= 2) was 0.02 mg l−1. The injection rate was 20 h−1. Glucose was determined satisfactorily in control sera and in real blood sera.