New Impedance Based Methodologies to Determine the Vial Heat Transfer Coefficient. Poster presentation at UK-PharmSci, 5-7th September 2017, Hatfield, UK PandyaBhaskar SmithGeoffrey 2020 <div>Cite as:</div><div>Pandya et al. (2017). New Impedance Based Methodologies to Determine the Vial Heat Transfer Coefficient. Poster presentation at UK-PharmSci, 5-7th September 2017, Hatfield, UK</div><div><br></div><div>Aims: To propose a new methodology to determine the vial heat transfer coefficient (Kv) and the endpoint of primary drying. Methods: Convergence of the peak imaginary capacitance (C"PEAK) and the high frequency permittivity, C'(100 kHz) was used as a new method to calculate the drying rate and Kv and the time profile of C'(100 kHz) was used to determine the endpoint. Results: Convergence was true only within the first 5 % of ice sublimation; C'(100 kHz) plateau coincided with the visual endpoint; Conclusions: Kv should be calculated only within the first 5% of primary drying and C'(100 kHz) can be followed to detect the endpoint.<br></div>