Determination of bromine in blood serum by 125I excited x-ray fluorescence

A radioisotope excited XRF method based on the use of five 10-mCi 125I point sources arranged in a newly designed configuration is applied to the bromine determination in very small blood serum samples (less than or equal to 50 microL). The possibility of determination of 0.05 micrograms Br in blood serum during 100 s counting time with a standard deviation of +/- 10% is described. The simplicity and low cost of the present method are major advantages over the other nondestructive methods and render it suitable for medical laboratories.