Rapid HPLC determination of total homocysteine and other thiols in serum and plasma: sex differences and correlation with cobalamin and folate concentrations in healthy subjects

• Published in: Clinical chemistry (Baltimore, Md.) Vol. 40; no. 6; pp. 873 - 881
• Main Authors: Jacobsen, DW, Gatautis, VJ, Green, R, Robinson, K, Savon, SR, Secic, M, Ji, J, Otto, JM, Taylor, LM, Jr
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Washington, DC Am Assoc Clin Chem 01.06.1994; American Association for Clinical Chemistry
• Subjects: Adult; Aged; Biological and medical sciences; Chromatography, High Pressure Liquid - methods; Chromatography, High Pressure Liquid - statistics & numerical data; Cysteine - blood; Dipeptides - blood; Female; Folic Acid - blood; Homocysteine - blood; Humans; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Microchemistry; Middle Aged; Miscellaneous. Technology; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Reference Values; Sensitivity and Specificity; Sex Characteristics; Sulfhydryl Compounds - blood; Vitamin B 12 - blood; Sulfur containing aminoacid; Human; Thiohydroxyl group; Vitamin; Clinical biology; HPLC chromatography; Exploration; Cobalamine; Sexual dimorphism; Folate; Quantitative analysis
• ISSN: 0009-9147; 1530-8561
• DOI: 10.1093/clinchem/40.6.873

High-performance liquid chromatography with fluorescence detection has been utilized for the rapid determination of total homocysteine, cysteine, and cysteinylglycine in human serum and plasma. Our earlier procedure (Anal Biochem 1989;178:208), which used monobromobimane to specifically derivatize thiols, has been extensively modified to allow for rapid processing of samples. As a result, > 80 samples a day can be assayed for total homocysteine, cysteine, and cysteinylglycine. The method is sensitive (lower limit of detection < or = 4 pmol in the assay) and precise (intra- and interassay CV for homocysteine, 3.31% and 4.85%, respectively). Mean total homocysteine concentrations in plasma and serum were significantly different, both from healthy male donors (9.26 and 12.30 mumol/L, respectively; P < 0.001) and healthy female donors (7.85 and 10.34 mumol/L, respectively; P < 0.001). The differences in total homocysteine between sexes were also significant (P = 0.002 for both plasma and serum). Similar differences were found for cysteine and cysteinylglycine. We found a significant inverse correlation between serum cobalamin and total homocysteine in men (P = 0.0102) and women (P = 0.0174). Serum folate also inversely correlated with total homocysteine in both sexes.