Determination of fluorine-ion in human urine by ion chromatography method

Objective: To establish a method to determine fluorine ion in human urine by ion chromatography method. Methods: The samples were centrifuged, diluted and processed by C(18) solid-phase column, potassium hydroxide as mobile phase, gradient elution, separated by AS(15), and determined by anion conductivity detector. Results: The linear correlation coefficient of fluoride ion in the range of 0.02-10.00 mg/L was more than 0.999. The lowest detection limit of urinary fluoride was 0.06 mg/L (in 3 ml urine) . The recoveries of the method were 96.9%-99.5%, the inter batch precision range was 0.40%-2.89%. The intra batch precision was from 1.01 to 7.23%. Fluoride samples could be stored for 7 days at room temperature and 4 ℃, and be stored for 14 days at -20 ℃. Conclusion: Determination of fluoride in urine by ion chromatography, the method could meet the requirement in GBZ/T 210.5-2008.