CONTINUOUS FLOW ENZYME-CATALYZED POLYMERIZATION IN A MICROREACTOR:  REACTIVITY AND STABILITY OF ENZYMES

Santanu Kundu and Kathryn L. Beers

Polymers Division, National Institute of Standard and Technology, Gaithersburg, MD 20899

Enzymes immobilized on solid supports are increasingly used for greener, more sustainable chemical transformation processes. In this study, we used microreactors to study enzyme-catalyzed ring opening polymerization of e-caprolactone to polycaprolactone.  A novel microreactor design enabled us to perform these heterogeneous reactions in continuous mode, in organic media, and at elevated temperatures.  Using microreactors, we achieved faster polymerization and higher molecular mass compared to using batch reactors. While this study focused on polymerization reactions, it is evident that similar microreactor-based platforms can readily be extended to other enzyme-based systems, for example, high throughput screening of new enzymes and to precision measurements of new processes where continuous flow mode is preferred.  One of the critical parameters for enzyme-catalyzed reactions is leaching of enzymes from solid beads into products. We investigated stability of the adsorbed enzyme on the model hydrophobic surfaces using a Quartz Crystal Microbalance (QCM). QCM measurements may also provide insight on the reactivity of the polymer chain at the enzyme active site.