title: Toward Microbioreactor Arrays: A Slow-Responding Oxygen Sensor for Monitoring of Microbial Cultures in Standard 96-Well Plates.
abstract: In this study, a slow-responding chemo-optical sensor for dissolved oxygen (DO) integrated into a 96-well plate was developed. The slow response time ensures that the measured oxygen value does not change much during plate transport to the microplate reader. The sensor therefore permits at-line DO measurement of microbial cultures. Moreover, it eliminates the necessity of individual optical measurement systems for each culture plate, as many plates can be measured successively. Combined with the 96-well format, this increases the experimental throughput enormously. The novel sensor plate (Slow OxoPlate) consists of fluorophores suspended in a polymer matrix that were placed into u-bottom 96-well plates. Response time was measured using sodium sulfite, and a t90 value of 9.7 min was recorded. For application, DO values were then measured in Escherichia coli and Saccharomyces cerevisiae cultures grown under fed-batch-like conditions. Depending on the DO sensor's response time, different information on the oxygenation state of the culture plate was obtained: a fast sensor variant detects disturbance through sampling, whereas the slow sensor indicates oxygen limitation during incubation. A combination of the commercially available OxoPlate and the Slow OxoPlate enables operators of screening facilities to validate their cultivation procedures with regard to oxygen availability.
authors.affiliation: Chair of Bioprocess Engineering, Technische Universität Berlin, Berlin, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Glauche
authors.affiliation: PreSens Precision Sensing GmbH, Regensburg, Germany.
authors.forename: Gernot T
authors.initials: GT
authors.lastname: John
authors.affiliation: PreSens Precision Sensing GmbH, Regensburg, Germany.
authors.forename: Sarina
authors.initials: S
authors.lastname: Arain
authors.affiliation: Chair of Bioprocess Engineering, Technische Universität Berlin, Berlin, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Knepper
authors.affiliation: BioSilta Europe GmbH, Berlin, Germany.
authors.forename: Antje
authors.initials: A
authors.lastname: Neubauer
authors.affiliation: Organobalance GmbH, Berlin, Germany.
authors.forename: Detlef
authors.initials: D
authors.lastname: Goelling
authors.affiliation: Organobalance GmbH, Berlin, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Lang
authors.affiliation: Chair of Measurement and Control, Technische Universität Berlin, Berlin, Germany.
authors.forename: Norman
authors.initials: N
authors.lastname: Violet
authors.affiliation: Chair of Measurement and Control, Technische Universität Berlin, Berlin, Germany.
authors.forename: Rudibert
authors.initials: R
authors.lastname: King
authors.affiliation: Chair of Bioprocess Engineering, Technische Universität Berlin, Berlin, Germany peter.neubauer@tu-berlin.de.
authors.forename: Peter
authors.initials: P
authors.lastname: Neubauer
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D001709:Biotechnology / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D005456:Fluorescent Dyes / Q000032:analysis / Q000378:metabolism; D057166:High-Throughput Screening Assays / Q000295:instrumentation* / Q000379:methods; D010100:Oxygen / Q000032:analysis* / Q000378:metabolism
chemical_list: D005456:Fluorescent Dyes; D010100:Oxygen
keywords: high throughput; microbial cultures; oxygen sensor; response time