Microfluidic Reactors with Immobilized Enzymes for Biocatalytic Transformations

2 Microfluidic Reactors with Immobilized Enzymes for Biocatalytic Transformations 

Another category of enzymatic transformations in multiphase systems is enzymes immobilized on the reactor wall as presented in Table 10.4. Enzymes are advantageously used in immobilized form because this strategy allows for increased volumetric productivity and improves stability. Continuous mode of operation is employed in these systems. The approaches commonly used for immobilization in conventional multiphase biocatalysis can also be employed in microreactors such as covalent methods, cross-linked enzyme aggregates (CLEA), and adsorption methods. The experimental setups can either be chip-type reactors with activated charmel surface walls where enzyme binds, or enzyme immobilized monolith reactors, where a support is packed inside a capillary tube. 

This microreactor, called CLEA-based enzyme microreactor (CEM), prevents high pressure better than carrier-filled microreactors because of its hollow structure [121]. 

This microreactor enabled a highly enantioselective reaction for a racemic amino acid derivative. The integration of enzyme microreactor (CLEA-CEM) and microextractor provided efficient continuous production of optically pure amino acids. 

Enzyme immobilization by CLEA was also used by Hickey and others [156]. The aminoacylase enzyme was successfully immobilized in miniaturized flow reactors. 

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