Performance qualification (PQ) of taste sensing systems is mandatory for their use in pharmaceutical industry. According to ICH Q2 (R1) and a recent adaptation for taste sensing systems, non-specificity, log-linear relationships between the concentration of analytes and the sensor signal as well as a repeatability with relative standard deviation (RSD) values <4% were defined as basic requirements to pass a PQ.
In the present work, the αAstree taste sensing system led to a successful PQ procedure by the use of recent sensor batches for pharmaceutical applications (sensor set #2) and a modified measurement protocol. Log-linear relationships between concentration and responses of each sensor were investigated for different bitter tasting active pharmaceutical ingredients (APIs). Using the new protocol, RSD values <2.1% were obtained in the repeatability study. Applying the visual evaluation approach, detection and quantitation limit could be determined for caffeine citrate with every sensor (LOD 0.05–0.5 mM, LOQ: 0.1–0.5 mM). In addition, the sensor set marketed for food applications (sensor set #5) was proven to show beneficial effects regarding the log-linear relationship between the concentration of quinine hydrochloride and the sensor signal.
By the use of our proposed protocol, it is possible to implement the αAstree taste sensing system as a tool to assure quality control in the pharmaceutical industry.