Trace element studies on whole human cerebrospinal fluid with external beam PIXE

External beam PIXE analysis with a 2.4 MeV proton beam was used to determine the concentrations of K, Ca, Fe, Cu, Zn and Br in cerebrospinal fluid from patients having various disorders. The obtained total concentration ranges K 34,000-1,079,000, Ca 5300-81,300, Fe 40-1030, Cu 20-1650, Zn 15-1250 and Br 400-43,000 micrograms/kg are compared with the values given in the literature. In certain patients there were very high CSF bromine levels, but this was shown to be the result of taking medications presented as bromide salts. The possibility of using the method in clinical practice for CSF analysis is considered. The new method of preparing self-supporting films of the samples was used. This method was further optimized by investigating in detail the use of EDTA as a homogenizer.