Concentrations of quinolinic acid in cerebrospinal fluid measured by gas chromatography and electron-impact ionisation mass spectrometry: Age-related changes in a paediatric reference population

• Published in: Journal of chromatography. B, Biomedical sciences and applications Vol. 696; no. 1; pp. 53 - 58
• Main Authors: Dobbie, Michael S, Surtees, Robert A.H
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.08.1997; Elsevier Science
• Subjects: Adolescent; Age Factors; Biological and medical sciences; Cerebrospinal fluid (biochemistry, cytology, circulation, manometry). Intracranial pressure determination; Child; Child, Preschool; Gas Chromatography-Mass Spectrometry - methods; Humans; Infant; Infant, Newborn; Investigative techniques, diagnostic techniques (general aspects); Medical sciences; Quinolinic acid; Quinolinic Acid - cerebrospinal fluid; Quinolinic Acid - chemistry; Reference Standards; Reference Values; Reproducibility of Results; Sensitivity and Specificity; Quinolinic acid; Human; Biological fluid; Pediatrics; Nervous system diseases; Biological marker; Cerebrospinal fluid; Medical screening; Gas chromatography; Laboratory investigations; Clinical biology; Child; Mass spectrometry; Quantitative analysis
• DOI: 10.1016/S0378-4347(97)00221-1
• ISSN: 0378-4347; 1387-2273

A simple method for the determination of the excitotoxin, quinolinic acid (QUIN) in cerebrospinal fluid (CSF) is described. QUIN, in lyophilized samples, was silylated by N-methyl- N-( tert.-butyldimethylsilyl)trifluoroacetamide in a single-step reaction at 65 to 70°C to form a di- tert.-butyldimethylsilyl ester. Neither pre-purification of QUIN from CSF nor post-derivatisation sample clean-up was required. The derivatives were analysed by gas chromatography–electron impact mass spectrometry resulting in a prominent and characteristic [M−57] + fragment ion which was used for quantitation. 2,6-Pyridine dicarboxylic acid, a structural analog of QUIN, was used as the internal standard. The detection limits for injected standards are in the femtomole range. CSF QUIN was found to be age-related and three preliminary reference ranges for CSF QUIN were found: 0 to 1 years, 31±15 n M QUIN (mean±standard deviation); 1.1 to 3 years, 26±15 n M; 3.1 to 14 years, 14±9 n M.