van Staden J F, van Rensburg S D
Department of Chemistry, Faculty of Science, University of Pretoria, South Africa.
Analyst. 1991 Aug;116(8):807-10. doi: 10.1039/an9911600807.
Different microdiffusion techniques for the determination of ionic and ionizable fluoride in milk have been evaluated for measurement with a fluoride-selective sensor. This work culminated in a modified version of the hexamethyldisiloxane-acid diffusion technique where an increased amount of perchloric acid and sodium hydroxide seemed to be a prerequisite for accurate and precise results. The configuration of the fluoride-selective electrode was also modified by using an adapted microanalytical procedure to determine fluoride in small volumes (50 microliters each) and to avoid contamination between successive milk samples. The resultant procedure is free of interferences and is capable of measuring fluoride in milk at concentrations from 0.02 to 10.00 mg dm-3 with improved accuracy and precision compared with earlier work.
已对用于测定牛奶中离子态和可离子化氟化物的不同微扩散技术进行了评估，以便使用氟离子选择性传感器进行测量。这项工作最终形成了六甲基二硅氧烷 - 酸扩散技术的改进版本，其中增加高氯酸和氢氧化钠的用量似乎是获得准确和精确结果的先决条件。通过采用一种经过调整的微量分析程序，还对氟离子选择性电极的配置进行了改进，以测定小体积（每份50微升）中的氟化物，并避免连续牛奶样品之间的污染。与早期工作相比，所得程序无干扰，能够测量牛奶中浓度为0.02至10.00 mg dm-3的氟化物，且准确性和精密度有所提高。
