Colorimetric Determination of Calcium Ion with o-Cresolphthalein Complexone
Studies on the Automatic Analysis of Salt Manufacturing Samples (Part5)
1981 Volume 35 Issue 1 Pages 33-37
Details
1981 Volume 35 Issue 1 Pages 33-37
The authors made an investigation on Technicon's auto-analyzer by the colorimetric method o-cresolphthalein complexone (o-C.P.C.) reagent to determine automatically the calcium ion of salt manufacturing samples. The analytical method was as follows: After the pH of a sample was controlled with potassium phosphate solution (buffer solution), the o-C.P.C.reagent was added to the sample solution, and then a colored complex was formed. Calcium ion was determined by measuring the color intensity.
In this method, a linear relationship was obtained between the absorbance and the concentration of calcium ion in the range of 0-200mg/l.
This method has the same accuracy as the conventional EDTA method.The coefficient of varia-tion was below 4%, and the speed of analysis was consecutive 20 samples per hour.
