Determination of platinum in boron-containing glasses by neutron activation analysis

Neutron activation anslysis is the only analytical method that allows the determination of platinum in the concentration range below 1 ppM. Because of the high activity of the matrix the determination was done via the daughter product of 31 min /sup 199/Pt, /sup 199/Au which, due to its half-life of 3.15 d, can be chemically separated. A procedure for acid decomposition of the glass and chemical separation of the gold was worked out that can be performed within a reasonable time. As the boron content of many glasses causes a high neutron self- shielding, the self-shielding effect as a function of the matrix and the boron concentration was investigated. A procedure to reduce the self-shielding effect was also developed. Using the procedure described, platinum concentrations down to 0.1 ppM could be determined. (auth)