DIRECT DETERMINATION OF POTASSIUM IN HUMAN BLOOD-SERUM BY FLOW-INJECTION FLAME PHOTOMETRY WITH AUTOMATIC DILUTION

A method was developed for the automatic quantitative determination of potassium in serum: by flow injection analysis. The serum sample is d irectly introduced in the flow. The dilution with deionized water stre am is done automatically acid sequentially in the system to reach the adequate concentration to be introduced in the flame photometer. The r esults achieved with this method, for serum samples obtained in the Ho spital of the University, had been compared with those values of the H ospital laboratory that uses manual dilution and flame photometry. The results obtained by the two methods agree within at least +/-5%. Abou t 60 samples/hour can be easily analyzed by the method proposed in thi s work.