A RAPID METHOD FOR THE DETERMINATION OF HIPPURIC ACID IN URINE

Colorimetric determination of hippuric acid in urine and liver homogenate.

To a dried extract Containing hippuric acid (HA), 1.0 mL of acetic anhydride and 2.0 mL of 0.5% p-dlmethyiamlnobenzaldehyde (DAB) solution In pyridine were added, and the solution was kept at 40 O C for 1 h after thorough mlxing. The absorbance was then determlned at 458 nm agalnst a blank containing acetic anhydride, DAB, and pyridine. This method was in good agreement with Beer’s law within 1...

Direct colorimetric determination of hippuric acid in urine.

In 1963 Umberger and Fiorese (1) introduced a colorimetric method for HA,1 based on the color reaction of HA, dissolved in anhydrous pyridine, with BSC. Therefore, for applying their method to determine HA in urine, HA must first be extracted from the urine. We found that HA dissolved in water-pyridine (1:1, by vol) produces a red-orange color when BSC is added at room temperature. The absorpti...

A modified method for the determination of hippuric acid and free benzoic acid in the urine of cattle.

DEVELOPMENT OF A METHOD FOR THE DETERMINATION OF 4-HYDROXY-3-METHOXYMANDELIC ACID (VANILLYLMANDELIC ACID) IN URINE BY PAPER CHROMATOGRAPHY

We have developed a simple and precise paper chromatographic method for the determination of 4-hydroxy-3-methoxymandelic acid (VMA) in urine. Concentrations of VMA in patients with neuroblastoma were increased in comparison to controls. The linearity was excellent in the concentration range tested. The within-assay coefficient of variation for control and patient urine was less than 2.2%. ...

A method for the determination of formiminoglutamic acid in urine.

Formimino-L-glutamic acid, an intermediate in the metabolism of histidine (1, 2), accumulates in the urine of folic acid-deficient rats (37). The urinary formiminoglutamic acid has also been reported to be increased in macrocytic anemia of pregnancy and in patients treated with folic acid antagonists (8-10). These findings can be attributed to a lack of tetrahydrofolic acid (THF), since enzymat...