Long-term stability of PDMS-based microfluidic systems used for biocatalytic reactions

This paper reports on the changes of PDMS interface characteristics due to the long-term influence of aqueous alkaline solutions, which are frequently used fluids in biocatalytic reactions. Soft lithographic techniques were used to produce polymeric microfluidic systems containing a fluidic layer with multiple cavities for biocatalytic reactions and a pneumatic control layer. The surface energy, the surface roughness and the absorption of liquids on PDMS are analysed as they are important factors affecting the microfluidic current. The results obtained can be used to provide design guidelines for adapting PDMS-based microfluidic devices in long-term bio catalysis reactions.