Colorimetric determination of boric acid

Reproductive toxicology. Boric acid.

Boric acid (BA), widely used for both medicinal and nonmedicinal purposes, was known to adversely affect reproduction and fertility in rodents. NIOSH, in evaluating the literature prior to writing a Criteria Document, asked NIEHS to perform an RACB study on BA to generate both structural and functional data to be used for setting exposure criteria (Fail et al., Fundam Appl Toxicol 17:225-239 [1...

Boric Acid and Borates

Boric acid and its chemical relatives are pesticides that are derived from the element boron. Boron rarely occurs alone and is typically found in combination with other elements; common combinations are boric acid or borates.1 Unlike many pesticides which are synthetic compounds,2 boric acid and related pesticides are naturally occurring compounds.1 Boron compounds are widely found in rivers, s...

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...

The Colorimetric Determination of Lactic Acid in Biological Material