Optimized Determination of Urine Fluorine by Ion Selected Electrodes

Objective To optimize the rapid method for measuring fluoride concentration in urine by ion selected fluoride electrodes. Methods The NaOH amount and mass were calculated to confect the HAc-NaAc buffer TISAB solution; the evaluations were discussed by studying the linear range, sensitivity, recovery and precision. Results The theoretical amount calculation of NaOH got the simple buffer solution preparation and the samples were advised and made of 10.00 ml urine and 25 ml TISAB, the liquid transfer error for both was decreased. The perfect lineal relation of fluoride concentrations were obtained in the range of 0.1-10.0 mg/L with the correlation coefficient above 0.999. The rates of recovery were 89%-114 %, the relative standard deviation was below 10 % and the lowest limit of detection was 0.08 mg/L. The response times varied from 0.5 to 5.3 min. Conclusion The fluoride electrodes method presents a low limit of detection, high sensitivity, accuracy and precision, without any interference and is applicable to the determination of fluoride in complicated urine samples.