不同生长期枸杞果中微量氟的快速测定

Rapid Determination of Micro Fluorine in Wolfberry Fruits at Different Growth Stages

研究枸杞果生长过程中氟含量的变化。采集郑州市区天然生长的同丛枸杞青果、黄果和红果,用超声波浸提,离子选择性电极浓度直读法快速测定样品中的微量氟。结果表明:枸杞果水分含量在成熟过程中逐渐增高;枸杞果氟含量在成熟过程中逐渐降低,青果、黄果、红果中氟含量依次为0.68、0.57、0.53μg/g;样品测定的RSD小于3%(n=5),加标回收率为97.0%～105.0%,该法简便快速、实用性强,利于推广普及。

In order to probe into the distribution characteristics of fluorine content in wolfberry fruits at different growth stages, green, yellow and red wolfberry fruits from the same cluster wildly growing in the east suburb of Zhengzhou were extracted with 1.0 mol/L HCl under ultrasonic assistance and the concentrations of micro fluorine in the extracts were directly given by fluorine ion selective electrode. It was showed that wolfberry fruits exhibited a gradual increase in moisture content during ripening, whereas fluorine content had an opposite change. The content of fluorine was 0.68μg/g in green wolfberry fruits, 0.57 μg/g in yellow wolfberry fruits and 0.53 μg/g in red wolfberry fruits. All the relative standard deviations （RSDs） of precision for 5 replicate determinations of green, yellow and red wolfberry fruits were smaller than 3%. The method spike recovery range was between 97.0% and 105.0%. Thanks to the merits of simplicity, rapidity and good practicality, this method deserves to be popularized.