Tunable Diode Laser Absorption Spectroscopy (TDLAS) Enabled SMART Freeze-Dryer Technology

Abstract

Tunable Diode Laser Absorption Spectroscopy (TDLAS) measurements combined with SMART Freeze-Dryer Technology enabled automated pharmaceutical lyophilization process development. The sensor measured water vapor temperature, density and flow velocity used to calculate water vapor mass flow rates (dm/dt). The dm/dt values were combined with a heat and mass transfer model of lyophilization to enable real-time determinations of product temperature during sublimation. The temperatures combined with a process development algorithm produced efficient freeze-drying cycles during a single lyophilization experiment. The SMART-TDLAS Freeze-Dryer Technology was used to dry placebo formulations in laboratory and pilot-scale lyophilizers, demonstrating application at multiple scales.