Potential of Mid-Infrared Spectroscopy for On-Line Monitoring of Mammalian Cell Culture Medium Components

Abstract

This study proposed a methodology to evaluate the potential of midinfrared (MIR) spectroscopy as a process analytical technology (PAT) tool for in situ (in-line) monitoring of cell culture media constituents, paving the way for on-line bioprocess monitoring and control of mammalian cell cultures. The methodology included a limit of detection (LOD) analysis and external influence investigation in addition to the calibration model development. The LOD analysis in the initial step provided a detailed procedure by which to evaluate the monitoring potential of the instrument of choice, for the application in question. The external influence study highlighted the potential difficulties when applying this technique to a typical mammalian cell culture. A comparative investigation between a fixed conduit immersion probe and flexible fiber-optic immersion probe was also carried out. Limitations associated with the use of MIR spectroscopy in the cell culture environment were also examined. A preliminary investigation, on components typically found in mammalian cell cultures, involving spectral characterization and limit of detection analysis was completed. It was evident at this initial stage that glutamine, could not be accurately detected at levels typically found in a mammalian cell culture medium. Results for glucose and ammonia, however, proved promising. A seven-concentration-level experimental design was used, and partial least squares regression employed, to develop calibration models. Optimized model results echoed the results of the preliminary analysis with the percentage error of prediction for glucose as low as 6.03% with the fixed conduit probe and glutamine having a higher error of 63.06% for the same probe. Comparison of the model results obtained from both probes supported the fixed conduit as the more accurate of the two probes for this experimental setup. The effect of external influences on the MIR spectra and hence the concentrations predicted by the model were also examined. These were subjected to statistical analysis to determine the significance of the effect. This study demonstrates that MIR spectroscopy as a PAT tool has limited potential for mammalian cell culture monitoring due to low concentrations of analytes present and outlines a method to allow the system to be evaluated.

Recent Progress in Lab-On-a-Chip Systems for the Monitoring of Metabolites for Mammalian and Microbial Cell Research

“…Here we focus on fluorescent and colourimetric methods as these are the main optical sensing approaches used for cellular metabolite detection on LOC devices. However, other methods such as Raman and Infrared (IR) spectroscopy technologies have been externally implemented for the detection of metabolites with high sensitivities and requiring low sample volumes [37,38,39].…”

Spectroscopic methods and their applicability for high‐throughput characterization of mammalian cell cultures in automated cell culture systems

“…As in the case of NIR spectroscopy, applications for MIR spectroscopy in the quality control of cell culture media have been demonstrated. These analyses were also performed offline and were able to quantify the components glucose, glutamine, glutamate, lactate, sodium carbonate, potassium phosphate, and ammonium sulfate . An overview of some possible applications of MIR spectroscopy is shown in Table .…”

“…In the field of mammalian cell cultures, ATR probes are mainly used for online measurements [28]. These online sensors have been used, for [69] example, to quantify glucose and acetates [66], as well as fructose, glucose, ethanol, and organic acids in CHO cultivations [67]. Offline, in the dried supernatant of CHO cultures, the determination of glucose, lactate, and antibody concentration has also been demonstrated [68].…”

Integrating systems analysis and control for implementing process analytical technology in bioprocess development

“…Nevertheless, there are several examples where researchers have tried to incorporate real‐time sensors (PAT tools) to monitor at least one of the many physiological properties of culture. For example, use of NIRS for monitoring a critical nutrient ratio for lipstatin fermentation by Streptomyces toxitricini , MIRS for online monitoring of mammalian cell culture medium components, Raman spectroscopy for real‐time monitoring of multiple parameters in mammalian cell culture, biocalorimetry for reliable biomass monitoring, and dielectric spectroscopy to monitor live biomass . BaychroMAT, a commercial product of Bayer Technology Services GmbH, has been created for long‐term perfusion culture of mammalian cells .…”