Enzymatic microreactors could be used in numerous applications such as sensing devices, energy production, chemical synthesis and degradation, and environmental cleanup. An inherent advantage of enzymes, when compared to chemical reactors, is that the desired reactions occur at ambient temperatures and pressures. We seek to use these advantages in enzymatic reactors.
Enzymes are the nano-machines of cells. Enzymes have been steadily improved for eons by Darwinian evolution and more recently by the use of recombinant DNA technologies. Enzymes are known to catalyze more than 5000 diverse chemical reactions. Enzymatic reactions occur at ambient temperatures and pressures, while chemical catalysts frequently require robust reaction vessels containing dangerous solvents maintained at extremely high temperatures and pressures. Accordingly, the simplified reaction conditions of enzymatic reactors require less complex engineering than catalytic reactors. Therefore our focus is the development of the capability to build enzymatic micro-reactors. Production of a successful single channel reactor represents a first step toward creating machines that mimic complex, multi-step chemical reaction pathways. The goal is to produce large quantities of a recombinant enzyme, and then link the enzyme (without destroying its activity) to a suitable surface so that we can exploit the high mass transfer available with microtechnology to rapidly process substrate to product.
The revolution in recombinant DNA technology means that almost any enzyme can be produced in large quantities. The steps involved are: obtain the gene coding for the desired enzyme, transfer the gene to an expression vector, transform cells with the vector, grow the transformed cells under conditions that induce enzyme expression, and then purify the desired enzyme. We have extensive with these procedures, as well as the necessary equipment to grow the cells and purifiy active enzymes. Recombinant DNA technology also enables production of enzyme variants engineered for altered enzymatic activity, or production of enzymes that contain specific sequences designed to facilitate attachment of the enzyme to a particular surface. Once the desired enzyme is produced, it is necessary to link it to a microporous surface while retaining the enzymatic activity. The enzymatic reactor is then constructed around this material.
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