Kahama R W, Damen J J, ten Cate J M
Department of Cariology Endodontology Pedodontology, Academic Centre for Dentistry Amsterdam ACTA, The Netherlands.
Analyst. 1997 Aug;122(8):855-8. doi: 10.1039/a702175e.
The concentrations of diffusible and total fluoride in cows' milk samples from areas with widely different fluoride levels in drinking water were determined using a fluoride electrode. The diffusible fluoride was determined by direct hexamethyldisiloxane microdiffusion while for total fluoride, samples were subjected to either open ashing or digestion with proteolytic enzymes before microdiffusion. Magnesium nitrate was studied as a new fixative for milk during open ashing and compared with magnesium acetate. Diffusible fluoride ranged from 0.024 to 0.28 microgram ml-1 while total fluoride ranged from 0.05 to 0.31 microgram ml-1. The use of proteolytic enzymes before microdiffusion resulted in total fluoride measurement. It was concluded that all fluoride in milk is inorganic in nature with the bound fluoride being physically or chemically sequestered in the milk proteins. The proposed method is convenient for total fluoride analysis in milk.
使用氟电极测定了来自饮用水氟含量差异很大地区的牛奶样品中可扩散氟和总氟的浓度。可扩散氟通过直接六甲基二硅氧烷微扩散法测定，而对于总氟，样品在微扩散前进行敞口灰化或用蛋白水解酶消化。研究了硝酸镁作为敞口灰化过程中牛奶新固定剂的情况，并与醋酸镁进行了比较。可扩散氟的范围为0.024至0.28微克/毫升，而总氟的范围为0.05至0.31微克/毫升。微扩散前使用蛋白水解酶可进行总氟测定。得出的结论是，牛奶中的所有氟本质上都是无机的，结合氟在牛奶蛋白质中以物理或化学方式被隔离。所提出的方法便于进行牛奶中总氟的分析。
