Carbonisation technique for pre-treatment of biological materials in X-ray fluorescence spectrometry

Abstract

The carbonisation of biological material is proposed as a technique for facilitating the destruction of samples prior to the determination of elements by X-ray fluorescence (XRF) spectrometry. Biological materials heated at 300 °C for 1–2 h are carbonised and easily powdered to fine particles by using an agate mortar and pestle. Losses of inorganic elements from the samples during carbonisation at 300 °C for 1 h were less than 5% for sodium, magnesium, aluminium, chlorine, potassium, calcium, vanadium, chromium, manganese, cobalt, nickel, copper, zinc, bromine, rubidium and cadmium, but more than 30% for selenium and about 100% for mercury. The carbon remaining in the carbonised samples acts as a binder for the sample when discs are made.