Abstract: The biomolecule 2-phosphoglycolate (hydroxyphosphoacetate; I) was digested with acid phosphatase to yield glycolic acid which was derivatized with bis(trifluoromethyl)benzyl bromide then pivalic anhydride. The resulting O2-pivalyl-3',5'-bis(trifluoromethyl)benzylglycolate was applied to a HP Ultra 2 column (25 cm x 0.22 mm i.d.) coated with 5% phenyl methylsilicone gum (0.33 µm). Temperature programming was from 50-140°C at 45°C/min (held for 1 min), then to 140-170°C at 20°C/min (held for 2 min), then to 170-290°C at 60°C/min. He was the carrier gas; detection was by selected ion-monitoring at m/z = 159. The detection limit was 87 zmol I. Direct analysis of I by capillary electrophoresis with indirect fluorescence detection using fluorescein, and by FIA coupled with negative ion electrospray MS are described; detection limits were in the pmol range.

Abstract: Glycollate is determined by the action of L-2-hydroxyacid oxidase. The H2O2 produced is detected in the presence of peroxidase by use of an indicator reaction with 3-methyl-2-benzothiazoline hydrazine and NN-dimethylaniline. Urine samples are treated with activated charcoal before analysis to reduce interferences of reducing substances. Correction must be made for lactate in urine, which interferes. An accurate, precise and sensitive continuous-flow system, with use of enzyme immobilized on the inner surface of nylon tubing is described, but this is unsuitable for routine use because of the instability of the enzyme. A semi-automated procedure is described for the Cobas-Bio centrifugal analyzer. with use of enzyme in solution. Recovery by this method was 96% and within- and between-batch coefficient of variation were <2 and <5%, respectively. The normal reference interval for urinary excretion of glycollate is 0.13 to 1.31 mmol day-1.