Monitoring the dissolution of Active Pharmaceutical Ingredient and TPGS in real time via IR spectroscopy during the manufacturing of liquid dosage formulation.

Infrared spectroscopy is used to monitor the dissolution of the Active Pharmaceutical Ingredient (API) and an excipient (vitamin E - TPGS) during manufacturing of a liquid pharmaceutical formulation. The goal of the analysis is to explore options for real-time, on screen, and quantitative monitoring of these two components by using an iC10 instrument. As is common, the first step in the approach is to create respective calibration models for the two components and then apply those models on the spectra obtained from scale-up batches. Interestingly, while the API dissolves at the room temperature, TPGS dissolves at an acceptable rate at 50 °C so both temperatures have to be considered. It is shown that univariate models of sufficient accuracy can be developed with a straightforward applicability to the scale-up batches spectra and providing reasonably accurate estimates of the API and TPGS concentrations. Some limitations of the software on the employed instrument may diminish the prospect for the quantitative analysis of the components of interest in this formulation.