A simple automated determination of glucose in body fluids using an aqueous o-toluidine-acetic acid reagent

Abstract

An automated method for use with continuous flow systems is presented for the determination of glucose in deproteinized blood, urine or other body fluids. In the deproteinized samples, which can be stored for 24 h without alteration in their glucose values, the glucose content is determined using an o-toluidine-acetic acid reagent containing 40% of water. The sensitivity of the reagent is considerably raised by increasing the percentage of o-toluidine and by the addition of borax. These changes do not affect the high degree of specificity of the o-toluidine reaction for glucose. Dextran products do not give rise to falsely high values as has been the case with other o-toluidine-acetic acid reagents. Beer's law is obeyed up to a concentration of at least 30 mmoles/1. In routine use the method gives a standard deviation of 0.16 mmole/1 and a coefficient of variation of 2.8%. The improvements result in an effective, easily handled glucose reagent that is only moderately aggressive and lends itself both to automated and manual procedures.