Agricultural
chemicals are
labeled by the manufacturers, in collaboration with regulators, to specify the exact
methods and purposes of use that are allowed.
With this
labeling method, the intrinsically
labeled Golden Rice β - carotene showed a protonated molecule of m / z of Mβc + H + = 536 + 1 (representing unlabeled β - carotene) and a range of isotopomers with the most abundant showing an enrichment of 9 deuterium at Menrich - βc = Mβc + H + + 9 mass units (Figure 4) as analyzed by using the liquid chromatography / mass spectrometry with a positive atmospheric pressure
chemical ionization interface (the total m / z was Mβc + 9 + H + = 536 + 9 + 1 = m / z 546)(23).