000104878 001__ 104878
000104878 005__ 20190316233958.0
000104878 0247_ $$2doi$$a10.1366/000370207780807830
000104878 02470 $$2ISI$$a000246433600008
000104878 037__ $$aARTICLE
000104878 245__ $$aOn-Line Recalibration of Spectral Measurements Using Metabolite Injections and Dynamic Orthogonal Projection
000104878 269__ $$a2007
000104878 260__ $$c2007
000104878 336__ $$aJournal Articles
000104878 500__ $$aPCG-BiasCorrection
000104878 520__ $$aSpectrometers are enjoying increasing popularity in bioprocess monitoring due to their non-invasiveness and in-situ sterilizability. Their on-line applicability and high measurement frequency create an interesting opportunity for process control and optimization tasks. However, building and maintaining a robust calibration model for the on-line estimation of key variables of interest (e.g., concentrations of selected metabolites) is time-consuming and costly. One of the main drawbacks of using IR spectrometers on-line is that IR spectra are compromised by both long-term drifts and short-term sudden shifts due to instrumental effects or process shifts which might be unseen during calibration. The effect of instrumental drifts can normally be reduced by referencing the measurements against a background solution, but this option is difficult to implement for single-beam instruments due to sterility issues. In this work, in order to maintain the robustness of calibration models for single-beam IR and to increase resistance to process and instrumental drifts/offsets, planned spikes of small amounts of analytes were injected periodically into the monitored medium. The corresponding measured difference spectra were scaled-up and used as reference measurements for updating the calibration model in real-time based on Dynamic Orthogonal Projection (DOP). Applying this technique lead to a noticeable decrease in the standard error of prediction of metabolite concentrations monitored during an anaerobic fermentation of the yeast Saccharomyces cerevisiae.
000104878 6531_ $$aIn-situ bioprocess monitoring
000104878 6531_ $$amid-infrared
000104878 6531_ $$acalibration model robustness
000104878 6531_ $$areaction spiking
000104878 6531_ $$aon-line recalibration
000104878 6531_ $$amodel update
000104878 6531_ $$aDynamic Orthogonal Projection
000104878 700__ $$0240699$$g157493$$aDabros, Michal
000104878 700__ $$0240700$$g100071$$aAmrhein, Michael
000104878 700__ $$aGujral, Paman
000104878 700__ $$avon Stockar, Urs$$g106679$$0240951
000104878 773__ $$j61$$tApplied Spectroscopy$$k5$$q507-513
000104878 8564_ $$zURL
000104878 8564_ $$uhttps://infoscience.epfl.ch/record/104878/files/Recalibration%20DOB%20apls-61-05-03_15_21.pdf$$zn/a$$s411534
000104878 909C0 $$xU10179$$0252160$$pLGCB
000104878 909C0 $$pLA$$0252053
000104878 909CO $$qGLOBAL_SET$$pSTI$$particle$$ooai:infoscience.epfl.ch:104878
000104878 937__ $$aLGCB-ARTICLE-2007-008
000104878 973__ $$rREVIEWED$$sPUBLISHED$$aEPFL
000104878 980__ $$aARTICLE