[Evaluation and analysis on the micro-determination of fluoride in serum and finger blood]

The relationship of fluoride concentration between blood serum from vein and blood from finger tip was explored. Ninety people exposed to different levels of fluoride were selected. Group A was exposed directly to high level of fluoride, group B was exposed indirectly to median level of fluoride, group C was exposed to low level of fluoride and group D had no fluoride exposure. The fluoride concentration was determined by using a modified micro-fluoride electrode. The concentration of fluoride changed obviously with the delay of reservation. The fluoride concentrations of finger blood tested within one day from the four groups were different (A > B > C > D). The fluoride concentration in serum was lower compared with that in finger blood. The results showed that serum fluoride was correlated with finger blood fluoride within one day of reservation (r = 0.87). The regression equation was Y = 0.62X + 0.023. It was concluded that the determination of fluoride from finger blood could substitute for serum to reflect the level and degree of fluoride burden of body.