海水中活性磷酸盐的导数分光光度法测定——磷钼黄-罗丹明6G体系

Derivative Spectrophotometric Determination of Active Phosphate in Seawater

《海洋调查规范》采用磷钼蓝比色法测定海水中的活性磷酸盐,具有操作简便和标准曲线稳定的优点,但灵敏度较低,必须使用20cm光程吸收池和100ml的海水样品,因而当磷含量较低或水样浑浊时难以准确测定。我们用磷钒钼蓝-罗丹明B-明胶-OP体系的导数分光光度法代替之,发现灵敏度虽比前法高,但操作较烦,标准曲线的稳定性也不够理想。Hashitani等以磷钼酸-孔雀绿-PVA体系分光光度法测定海水中的磷含量,线性范围为10～250ng/

A first derivative spectrophotometric method is described for the determination of active phosphate in seawater, using yellow molybdopbosphate complex-rhodamine 6G system. The content of active phosphate is determined according to the sum of peak values measured at 515 nm and 540 nm. The relative standard deviations are 3. 0% and 11. 7% and the recovery is 100. 6%.