Biopharmaceutical industry aims for better surveilance over processes in drug manufacturing. The purpose of this work was to assess the possibilities of implementing process analytical technology (PAT) in laboratory scale bioprocessing with mammalian cell cultures and to determine the value of the introduced technology in better surveilance over the bioprocesses. We compared the classic ''off-line'' methods of cell growth monitoring by dyeing and counting with the ''on-line'' cell growth monitoring via capacitance measuring with ABER probes. The experiment was conducted with twelve bioprocesses in 5 litre single-use bioreactors. Two different CHO cell lines were grown there for twelve days. We monitored the capacitance throughout the entire process. We sampled and analyzed the culture daily on Vi-Cell cell counter. Results have shown high degrees of correlation between two methods of cell growth monitoring, especially during the early stages. High correlation betwen measurments was also observed during the temperature shift. A regression model for predicting temperature and pH shifts via capacitance was also made. We have shown that we can successfully predict and automatize shifts for a specific cell line under the right conditions by modeling. We have also expressed our thoughts about the impact of various factors like cell size and viability on capacitance measurements. Our current results confirm all of our hypotheses of ABER probes usage for successful and accurate ''on-line'' monitoring of cell growth. The work done contributes in advancing the implementation of PAT in laboratory scale bioprocessing with mammalian cell cultures.
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