Microreactors II

Massive parallelization of multi chamber selective reaction and separation in porous polymeric micro fluidic devices

Introduction

Developments in micro technology in the last two decennia have enabled researchers to dramatically scale down analytical equipment with the purpose of integrating sampling, sample transport, pre-treatment separation and detection on a ‘Lab-on-a-chip’ or µ-TAS. The concept of micro fluidic systems is a new and promising technology expected to revolutionize chemical and medical analysis and production systems. Generally liquids in micro space can be characterized by a large specific interface area and short diffusion distance. This short diffusion distance combined with laminar flows creates the possibility of in situ separation of products. Scaling up of eventual production is done by installing the chips in parallel while maintaining the advantageous system kinetics.

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A micro chemical system with integrated devices [1]


Project aim and description
This project’s aim is to develop micro-fluidic devices for gas-liquid as well as liquid-liquid systems where contact between different phases can be controlled and optimized. It involves enzymatic processes in polymeric micro-fluidic devices with a focus on reaction and separation. The devices are created by a process called Phase Separation Micro Molding [1]. This fabrication method offers the opportunity to quickly build and test new micro reactor designs.

Approach
Many reactions can be controlled by utilizing the permeability properties of the polymeric structure. The devices might be useful in for example enzymatic reactions that require stepwise addition of a reactant and additionally for integration of an enzymatic reaction with an efficient separation process. Cross-linking of proteins catalyzed by transglutaminase, an established cross-linking reaction, will be used as model system.

Besides enzymatic processes, virtual prototyping is used in order to provide detailed fluid dynamics and design rules for micro fluidic devices.

The polymeric structures have an unprecedented flexibility for a micro reactor. This advantageous property can be used for rolling and stacking of these chips in modular assemblies. By using this modular concept and smart distribution engineering, these micro systems offer technology that has the potential to drastically revolutionize existing production techniques.

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Concentration profiles of compounds involved in cross-linking. COMSOL FEMLAB model.

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Proof-of-principle of mass transport through the channel walls of a porous chip.

References

1. A. van den Berg (Ed.) and P. Bergveld (Ed.). Micro total analysis systems, 1994.

2. J. de Jong et al. Lab Chip, 2005. 5(11): p. 1240.

Acknowledgements

This research is part of ‘‘Process on a Chip’’ (PoaC) in collaboration with the Food Chemistry Group of Wageningen UR and the Membrane Technology Group of Twente University.