Premium
CORRELATIONS BETWEEN A FLUORIMETRIC and MASS FRAGMENTOGRAPHIC METHOD FOR THE DETERMINATION OF 3‐METHOXY‐4‐ HYDROXYPHENYLACETIC ACID and TWO MASS FRAGMENTOGRAPHIC METHODS FOR THE DETERMINATION OF 3‐METHOXY‐4‐ HYDROXYPHENYLETHYLENE GLYCOL IN CEREBROSPINAL FLUID
Author(s) -
Muskiet F. A. J.,
Jeuring H. J.,
Korf J.,
Sedvall G.,
Westerink B. H. C.,
Teelken A. W.,
Wolthers B. G.
Publication year - 1979
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/j.1471-4159.1979.tb04527.x
Subject(s) - chemistry , chromatography , correlation coefficient , reproducibility , cerebrospinal fluid , medicine , statistics , mathematics
One‐hundred and twenty‐two lumbar cerebrospinal fluid (CSF) samples were assayed for 3‐methoxy‐4‐hydroxyphenylacetic acid (HVA) by both a fluorimetric and mass fragmentographic method. The correlation coefficient (cc) and residual standard deviation (Syx) of the results were calculated as 0.966 and 23.3 ng/ml, respectively. If only samples containing less than 100ng/ml of HVA were considered, somewhat different values for cc and Syx were found (0.854 and 10.0 ng/ml, respectively). The data obtained by the fluorimetric method were consistently 17% lower than those obtained by the mass fragmentographic method. Spiking experiments resulted in 96.5 ± 7.8% recovery for the fluorimetric method, whereas the use of a deuterated internal standard was found to compensate completely for losses in the mass fragmentographic method. In addition the correlation between two different mass fragmentographic methods for the simultaneous determination of HVA and 3‐methoxy‐4‐hyd‐roxyphenylethylene glycol (MOPEG) in CSF was studied. The measurements were performed in different laboratories and resulted in correlation coefficients of 0.941 and 0.940 and residual standard deviations of 7.6 and 1.0 ng/ml for HVA and MOPEG, respectively. From all data we conclude that mass fragmentographic methods for the determination of catecholamine metabolites in CSF are superior to fluorimetric methods because of their selectivity, reproducibility and accuracy.