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Combinatorial Synthesis of and High-throughput Protein Release from Polymer Film and Nanoparticle Libraries

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Controlling pH in shake flasks using polymer-based controlled-release discs with pre-determined release kinetics.

Marco Scheidle¹, Barbara Dittrich, Johannes Klinger

¹Aachener Verfahrenstechnik - Biochemical Engineering, RWTH Aachen University, Sammelbau Biologie, Worringer Weg 1, D-52074 Aachen, Germany.

BMC Biotechnology

|March 25, 2011

Summary

This summary is machine-generated.

This study introduces novel polymer-based discs for controlled pH regulation in shake flask cultures. These discs reduce buffer needs, improving comparability between small-scale screening and large-scale fermentation processes.

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Area of Science:

Biotechnology
Microbial Cultivation
Process Development

Background:

Significant differences exist between small-scale screening and large-scale fermentation culture conditions.
Shake flask screenings often lack active pH control, relying on high buffer concentrations, which complicates process development.
pH is critical for microbial physiology, necessitating better control in screening environments.

Purpose of the Study:

To develop and present a novel, easy-to-use polymer-based controlled-release system for pH regulation in shake flasks.
To reduce the disparity in culture conditions between screening and large-scale fermentation.
To establish active pH control in shake flask experiments.

Main Methods:

Development of bio-compatible silicone discs embedding sodium carbonate (Na2CO3).
Utilizing a controlled-release system with pre-determined kinetics for gradual reagent release.
Cultivation of E. coli K12 and E. coli BL21 pRSET eYFP-IL6 in mineral media with glucose or glycerol as carbon sources.

Main Results:

Successful cultivation of E. coli strains using the controlled-release discs.
Reduction of buffer concentration by 50% when using glucose as the carbon source.
Complete omission of buffer requirement when using glycerol as the carbon source.

Conclusions:

The polymer-based controlled-release discs effectively maintain pH within the physiological range of microorganisms.
Buffer concentrations can be substantially reduced or eliminated, allowing better pH control than high buffer methods.
The system enhances the comparability of culture conditions between screening experiments and large-scale fermentation.