Validation of an industrial analytical sensor procedure realized with a SAW-based sensor system

Mass-sensitive sensors based on surface acoustic waves (Suface Acoustic Wave Devices, SAWs) can be used for qualitative as well as for quantitative determination of volatile organic compounds (VOCs). An analytical procedure for a SAW-based sensor system used for on-line process control of VOCs in pharmaceutical industry was developed. Analytical procedures applied in pharmaceutical development and production have to meet the requirements of good manufacturing practice (GMP) and therefore a validation in compliance with the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH)-guidelines had to be performed. It is shown that these procedures can be successfully validated as non-chromatographic procedures according to ICH-guidelines. As a typical example, the on-line control of a HPLC gradient former was investigated. In this particular case, the sensor system has to determine the actual composition of the mobile phase and furthermore it has to discriminate possible avoidance. The following analytical performance parameters are investigated to prove the validation of the analytical procedure: ∘ Specificity, ∘ Linearity, ∘ Limit of Detection and Quantitation, ∘ Accuracy, ∘ Precision, and ∘ Robustness.