Fig. 4
From: A new approach to off-gas analysis for shaken bioreactors showing high CTR and RQ accuracy
Performance of TOM in respiration measurement. Performance measurements were conducted as described by Schulte et al. [9]. Defined respiration activity was simulated by feeding a defined rate of CO2-enriched and O2-depleted gas to individual shake flasks, in the following referred to as OTRset and CTRset, respectively. A OTR and CTR determined with TOM at different OTRset and CTRset. Operation conditions: n = 180 rpm, d0 = 50 mm, VL = 10 mL water, 250 mL shake flask, T = 30 °C, tmeas (10 min duration of measurement phase) B RQ accuracy and reproducibility derived from OTR and CTR data in A. Data points in A and B are an average of 32 measurements from 8 individual shake flasks (4 measurements each flask). Standard deviations between individual flasks are presented as error bars. C Standard deviation of OTR and CTR determined with TOM at 21% O2, 0% CO2 and 5% CO2 at varying duration of measurement phase. Operation conditions: n = 180 rpm, d0 = 50 mm, VL = 20 mL water, 250 mL shake flask, T = 30 °C. D Standard deviation of OTR at varying relative filling volumes from 4–40% over duration of the measurement phase. The green oval indicates common operating conditions for microbial cultivations, the red oval indicates common operating conditions for mammalian and plant cell cultivations