数码成像比色法测定水样中的总磷

在酸性介质中,磷酸二氢钾与钼酸铵、酒石酸锑钾及抗坏血酸作用,生成蓝色的络合物。随着磷酸二氢钾浓度的增加,溶液颜色加深,其数码成像的RGB值亦随着磷酸二氢钾浓度的增加而增加,由此建立数码成像比色法(DIC)测定水样中总磷的新方法。考察了DIC法的影响因素和最佳反应条件。与钼酸铵分光光度法对照,该方法简单,快速。用于实际水样的测定,相对标准偏差为1.8%~3.4%,回收率为99.7%~102.5%,结果与分光度法一致。

Determination of Total Phosphorus in Water Sample by Digital Imaging Colorimetry

In acidic medium, the interaction of potassium dihydrogen phosphate with ammonium molybdate, potassium antimonyl tartrate and ascorbic acid result in blue compound complex. With increasing potassium dihydrogen phosphate concentration, the colour of solution and the RGB value of digital imaging are increased. Thus a novel assay of total phosphorus based on digital imaging colorimetry (DIC) has been developed. By comparing the DIC and the ammonium molybdate spectrophotometric method, involving factors on digital imaging and optimal conditions of same interacting system were discussed. The present novel assay is very simple and sensitive. Water samples were analyzed with the relative standard deviation (RSD) of 1.8%-3.4% and the recovery of 99.7%-102.5%. The results of determinations for water samples were consistent with those obtained by spectrophotometric method.