Detection and quantitative assay of 2-thiobarbituric acid from inert solid and solubilized samples by spectrometerAuthor(s): Ronald Bartzatt, Maggie Bartlett, Nancy Handler
The thiobarbiturates differ from other barbiturates in having a sulfur atom to replace the carbonyl oxygen at the C-2 position. The drug 2-thiobarbituric acid was soluble in 95% ethanol and 5% water for sensitive detection and measurement. All samples were examined at 340 nanometer wavelength. An ultraviolet-visible instrument with one centimeter glass cuvettes was suitable for this assay. Themolar extinction coefficient at 340 nmwas 349.9 Liter/(cm)(mole).An absorbance spectrum for 2-thiobarbituric acid in the identical solvent used for assay is accomplished. The standard curve ranged from0.0000457molar to 0.003830molar, an 84x fold concentration span. The lowest concentration assayed in this study was 0.006588 grams per liter (6.588E-06 grams per milliliter) with the highest concentration analyzed at 0.5521 grams per liter (5.5521E-04 grams per milliliter). This methodology was found to be consistent during analysis and highly sensitive.