title: Evaluation of a new annular capacitance probe for biomass monitoring in industrial pilot-scale fermentations.
abstract: The four-pin electrode capacitance probe has already shown to be a valuable tool for on-line monitoring viable biomass concentration in industrial-type fermentations. A new prototype annular probe was developed and its performance in real-time monitoring the concentration of viable cells during industrial pilot-scale fermentation for the production of an Active Pharmaceutical Ingredient (API) was investigated and compared to the four-pin probe. A set of 14 fermentations was monitored on-line: four of them with the four-pin probe, the remaining with the annular probe. The performance of both the annular and the four-pin electrode probe were compared against each other and against off-line measurements (viscosity and packed mycelial volume). The prototype annular probe showed to have higher signal intensity and sensitivity than the standard four-pin probe, with higher signal-to-noise ratio. Furthermore, its new design and construction proved to be easier to handle in an industrial environment.
authors.affiliation: Centre for Biological and Chemical Engineering, IST, Technical University of Lisbon, Av. Rovisco Pais, P-1049-001 Lisbon, Portugal.
authors.forename: Ana P
authors.initials: AP
authors.lastname: Ferreira
authors.forename: Luís M
authors.initials: LM
authors.lastname: Vieira
authors.forename: Joaquim P
authors.initials: JP
authors.lastname: Cardoso
authors.forename: José C
authors.initials: JC
authors.lastname: Menezes
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D002452:Cell Count / Q000295:instrumentation* / Q000379:methods; D018929:Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods; D049109:Cell Proliferation; D002470:Cell Survival / Q000502:physiology; D025802:Electric Capacitance; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005285:Fermentation / Q000502:physiology; D007218:Industrial Microbiology / Q000295:instrumentation* / Q000379:methods; D010865:Pilot Projects; D013302:Streptomyces / Q000166:cytology* / Q000254:growth & development*; D014159:Transducers