During the development and production of Active Pharmaceutical Ingredients (API), metal catalysts like Pt, Pd, Rh, V and other metals are often used. New regulations (USP 232, 233, ICH Q3D) strictly demand the absence of these metals in the final pharmaceutical product clearly defining permitted concentration limits. Producers are obliged to install modern analytical techniques and have to provide regular control for metal contaminants.
The analytical performance of the S4 T-STAR spectrometer was proven with glucose solutions from 0.1% to 5%. The solutions were spiked with 2 mg/kg of Cr, As, Pd, Cd and Sb and prepared on TXRF sample carriers without further treatment. The samples were analyzed with the S4 T-STAR applying two different excitation modes (Mo-K, W-Brems).
For screening purposes the direct analysis of a 5% glucose solution is possible. The dilution of the glucose solution leads to a more uniform sample layer and consequently to a better reproducibility of the measurement results.
For elements like Cd or Pd the W-Brems excitation leads to limits of quantification (LOQ) in the range of 0.1 to 0.4 mg/kg for diluted glucose solutions.
An even higher sensitivity provides the Mo-K excitation, which allows the quantification of elements like Cr, V, As or Pt at low ppb levels.