DETERMINATION OF P-HYDROXYPHENYLGLYCINE BY REACTION WITH O-PHTHALALDEHYDE USING A FLOW-INJECTION FLUOROMETRIC PROCEDURE

In the present study, new flow injection procedures for the determinat ion of p-hydroxyphenylglycine using either photometric or fluorimetric detection are proposed. The methods are based on the reaction of the amino acid with o-phthalaldehyde and 2-mercaptoethanol. The calibratio n graphs based on peak area were linear in the ranges 20-300 ng ml(-1) with fluorimetric detection and 5-60 mu g ml(-1) using the photometri c mode. The detection limit calculated for the fluorimetric procedure was 10 ng ml(-1). The method was applied to the determination of the f ree p-hydroxyphenylglycine present in industrial pharmaceutical sample s of a Dane salt. (C) 1997 Elsevier Science B.V.