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Evidence-based guidelines for controlling pH in mammalian live-cell culture systems.

ABSTRACT: A fundamental variable in culture medium is its pH, which must be controlled by an appropriately formulated buffering regime, since biological processes are exquisitely sensitive to acid-base chemistry. Although awareness of the importance of pH is fostered early in the training of researchers, there are no consensus guidelines for best practice in managing pH in cell cultures, and reporting standards relating to pH are typically inadequate. Furthermore, many laboratories adopt bespoke approaches to controlling pH, some of which inadvertently produce artefacts that increase noise, compromise reproducibility or lead to the misinterpretation of data. Here, we use real-time measurements of medium pH and intracellular pH under live-cell culture conditions to describe the effects of various buffering regimes, including physiological CO₂/HCO₃ ^- and non-volatile buffers (e.g. HEPES). We highlight those cases that result in poor control, non-intuitive outcomes and erroneous inferences. To improve data reproducibility, we propose guidelines for controlling pH in culture systems.

SUBMITTER: Michl J

PROVIDER: S-EPMC6486606 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Evidence-based guidelines for controlling pH in mammalian live-cell culture systems.

Michl Johanna J Park Kyung Chan KC Swietach Pawel P

Communications biology 20190426

A fundamental variable in culture medium is its pH, which must be controlled by an appropriately formulated buffering regime, since biological processes are exquisitely sensitive to acid-base chemistry. Although awareness of the importance of pH is fostered early in the training of researchers, there are no consensus guidelines for best practice in managing pH in cell cultures, and reporting standards relating to pH are typically inadequate. Furthermore, many laboratories adopt bespoke approache ...[more]

PMID: 31044169

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Dataset Information

Evidence-based guidelines for controlling pH in mammalian live-cell culture systems.

Publications

Evidence-based guidelines for controlling pH in mammalian live-cell culture systems.

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