Bioreactors monitoring and control with high-throughput in-situ spectroscopic tools
Team: João Lopes, Mafalda Sarraguça, Ricardo Páscoa
Biotechnological processes are crucial to the development of any economy striving to ensure a relevant position in future markets. The cultivation of microorganisms in bioreactors is one of the most important unit operations of biotechnological processes, and real-time monitoring of bioreactors is essential for effective bioprocess control.
Ideal sensors for real-time monitoring of bioreactors should be fast, sensitive, non-destructive and robust. They should also generate multi-analyte data without analyte consumption, should not require sampling, should not interfere with culture metabolism and should be resistant to the harsh, mixed, sometimes aerated, and often sterile environments in bioreactors. In this context, spectroscopy can be very useful in bioprocess monitoring and control and several spectroscopic techniques, generally coupled to optical fibers, have been investigated for different in-situ applications, covering different wavelength ranges, including ultraviolet–visible (UV–Vis), near infrared (NIR), mid infrared (MIR), Raman, and fluorescence spectroscopy.
Spectroscopic bioprocess monitoring provides series of spectra that constitute large data sets with much lower information content than data volume and from which meaningful information should be rapidly extracted. The non-selectivity of spectroscopic methods, associated with the high collinearity of many of the measured variables and with the need to understand the relevant relationships among those variables, has led to the application of multivariate data analysis and other mathematical tools, i.e. chemometrics, to spectral data to reduce the large number of variables and to support process analysis, understanding, and troubleshooting. These tools can be applied at sample level (i.e., process monitoring), batch level (i.e., process supervision), and overall process or plant level (i.e., PAT).
- Lourenço ND, Lopes JA, Almeida CF, Sarraguça MC, Pinheiro HM* (2012) Bioreactor monitoring with spectroscopy and chemometrics: a review, Anal. Bioanal. Chem., 404, 1211-1237
- Sarraguça MC, Paulo A, Alves MM, Dias AMA, Lopes JA, Ferreira EC* (2009) Quantitative monitoring of an activate sludge reactor using on-line UV-visible and near infrared spectroscopy, Anal. Bioanal. Chem., 395, 1159-1166
- Páscoa R, Lopes JA*, Lima JLFC (2008) In situ near infrared monitoring of activated dairy sludge wastewater treatment processes, Journal of Near Infrared Spectroscopy, J. Near Infrared Spec., 16(4), 409-419
- Dias AMA*, Moita I, Alves MM, Ferreira EC, Páscoa R, Lopes JA (2008) Activated sludge process monitoring through in-situ near-infrared spectral analysis, Water Sci. Technol., 57(10), 1643-1650