Enzyme Kinetics in Microreactors

Another enzyme that was studied extensively in microreactors to determine kinetic parameters is the model enzyme alkaline phosphatase. Many reports have appeared that differ mainly on the types of enzyme immobilization, such as on glass [413], PDMS [393], beads [414] and in hydrogels [415]. Kerby et al. [414], for example, evaluated the difference between mass-transfer effects and reduced effidendes of the immobilized enzyme in a packed bead glass microreactor. In the absence of mass-transfer resistance, the Michaelis-Menten kinetic parameters were shown to be flow-independent and could be appropriately predicted using low substrate conversion data. 

Moore et al. [419] used surface-enhanced resonance Raman scattering to detect the activity of hydrolases at ultralow levels. The method was used to rapidly screen the relative activities and enantioselectivities of 14 enzymes including lipases, esterases and proteases. In the current format, the sensitivity of this technique was sufficient to detect 500 enzyme molecules, thus offering the potential to 

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