Fluorometric measurement of serum magnesium with a centrifugal analyzer.
We developed a rapid fluorometric assay for measurement of serum magnesium using the ligand, 8-hydroxy-quinoline-5-sulfonate and adapted the procedure to the Multistat Fluorescence Light Scattering Centrifugal Analyzer. The standard curve extends from 0.26 to 4.11 mmol/l. There was no interference from calcium or inorganic phosphorus at concentrations of 4.95 and 5.0 mmol/l, lead, iron, zinc or copper at twice the normal levels found in serum, bilirubin at concentrations of 10 mg/dl, or lipemic samples with triglyceride concentrations of 2400 mg/dl. Citrate and EDTA lowered magnesium concentrations in serum. Analytical recovery of magnesium added to four serum specimens averaged 97%. Between-run and within-run precision of the assay gave CVs which ranged from 2.9 to 7.6%. Magnesium concentrations, measured by our fluorometric procedure, were compared with those obtained by atomic absorption and colorimetric procedures. Correlation coefficients of 0.91 and 0.88 were obtained.
D001322:Autoanalysis / Q000295:instrumentation; D003124:Colorimetry; D005069:Evaluation Studies as Topic; D005470:Fluorometry / Q000295:instrumentation; D006801:Humans; D008274:Magnesium / Q000097:blood*; D015125:Oxyquinoline / Q000031:analogs & derivatives; D013054:Spectrophotometry, Atomic; D013223:Statistics as Topic
D015125:Oxyquinoline; C013053:8-hydroxyquinoline-5-sulfonic acid; D008274:Magnesium