title: Comparison of Fiber Optic and Conduit Attenuated Total Reflection (ATR) Fourier Transform Infrared (FT-IR) Setup for In-Line Fermentation Monitoring.
abstract: The performance of a fiber optic and an optical conduit in-line attenuated total reflection mid-infrared (IR) probe during in situ monitoring of Penicillium chrysogenum fermentation were compared. The fiber optic probe was connected to a sealed, portable, Fourier transform infrared (FT-IR) process spectrometer via a plug-and-play interface. The optical conduit, on the other hand, was connected to a FT-IR process spectrometer via a knuckled probe with mirrors that had to be adjusted prior to each fermentation, which were purged with dry air. Penicillin V (PenV) and its precursor phenoxyacetic acid (POX) concentrations were determined by online high-performance liquid chromatography and the obtained concentrations were used as reference to build partial least squares regression models. Cross-validated root-mean-square errors of prediction were found to be 0.2 g L-1(POX) and 0.19 g L-1(PenV) for the fiber optic setup and 0.17 g L-1(both POX and PenV) for the conduit setup. Higher noise-levels and spectrum-to-spectrum variations of the fiber optic setup lead to higher noise of estimated (i.e., unknown) POX and PenV concentrations than was found for the conduit setup. It seems that trade-off has to be made between ease of handling (fiber optic setup) and measurement accuracy (optical conduit setup) when choosing one of these systems for bioprocess monitoring.
authors.affiliation: Institute of Chemical Technologies and Analytics, TU Wien, Vienna, Austria.
authors.forename: Cosima
authors.initials: C
authors.lastname: Koch
authors.affiliation: Christian Doppler Laboratory for Mechanistic and Physiological Methods for Improved Bioprocesses, TU Wien, Vienna, Austria.
authors.forename: Andreas E
authors.initials: AE
authors.lastname: Posch
authors.affiliation: Christian Doppler Laboratory for Mechanistic and Physiological Methods for Improved Bioprocesses, TU Wien, Vienna, Austria.|Institute of Chemical Engineering, TU Wien, Vienna, Austria.
authors.forename: Christoph
authors.initials: C
authors.lastname: Herwig
authors.affiliation: Institute of Chemical Technologies and Analytics, TU Wien, Vienna, Austria bernhard.lendl@tuwien.ac.at.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Lendl
mesh_terms: D000085:Acetates / Q000032:analysis / Q000378:metabolism; D019149:Bioreactors; D001709:Biotechnology / Q000295:instrumentation*; D004867:Equipment Design; D005285:Fermentation / Q000502:physiology*; D005336:Fiber Optic Technology / Q000295:instrumentation / Q000379:methods*; D016018:Least-Squares Analysis; D010404:Penicillin V / Q000032:analysis / Q000378:metabolism; D010408:Penicillium chrysogenum / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared / Q000295:instrumentation / Q000379:methods*
chemical_list: D000085:Acetates; C415326:phenoxyacetic acid; D010404:Penicillin V
keywords: FT-IR; Fourier transform infrared; PAT; Penicillium chrysogenum; Process analytical tool; in-line monitoring; multivariate calibration