Determination of titanium dioxide supplements in different matrices using two methods involving photometer and inductively coupled plasma optical emission spectrometer measurements.

Titanium dioxide (TiO2) is a viable marker in digestibility studies using different animal species. The photometrical analysis is based on an intense orange colour following the addition of hydrogen peroxide to an acid solution. The measurement using inductively coupled plasma optical emission spectrometry (ICP-OES) is a method for analysing more than one element from the same sample preparation. The present study was conducted to investigate whether an established ICP-OES element analysis following acid-based hydrolysis is appropriate for titanium analysis. Defined amounts of TiO2 were added to samples obtained in studies with cows, pigs and turkeys and recoveries were determined. It was shown that supplemented TiO2 can be determined in samples of feeds, faeces or excreta, and digesta using a method based on photometric or ICP-OES measurement. The differences between the true and measured titanium concentrations indicate that using the ICP-OES method leads to a higher accuracy of determination.