Mass fragmentographic determination of homovanillic acid in tissues and body fluids using the deuterium labeled species as internal standard

Mass fragmentographic methods for determination of 4-hydroxy-3-methoxyphenyl acetic acid (HVA) in human cerebrospinal fluid (CSF), urine, blood plasma and mouse brain were developed. After isolation by extraction or by Amberlite XAD-2 chromatography the HVA was converted to the heptafluorobutyryl methyl ester derivative and analyzed using the 2, 2 dideutero-2 (4-hydroxy-3-methoxy-2, 5, 6-trideuterophenyl) acetic acid (HVA-d₅) as an internal standard. The values (mean ± coefficient of variation) obtained on repetitive analyses of the same sample were for human CSF 0.42 nmole/ml ± 1.5% (n = 10), human plasma 48 pmole/ml ± 4.5% (n = 15), human urine 20 nmole/ml ± 5.4% (n = 10) and mouse brain 1.2 nmole/g ± 0.6% (n = 12). The results demonstrate that the use of HVA-d₅ as an internal standard provides high precision and the necessary sensitivity for the mass fragmentographic determination of HVA in small amount of tissue and body fluids.