Besides its use in enzyme characterization, the method can be applied to the development of process control strategies.Īn enzyme immobilized within a porous solid support is sequestered from the surrounding bulk solution. The effect of concentration gradients between solid particle and liquid bulk on enzyme performance is made evident and quantified.

We show measurements of pH and with spatiotemporal resolution, using in operando analysis for immobilized preparations of industrially important enzymes. We describe analytical principles applied to immobilized enzymes and focus on the determination of pH and the O 2 concentration. Herein we review approaches by opto-chemical sensing to determine the internal milieu of enzymes immobilized in porous particles. The deepened understanding thus acquired is critical for the rational development of immobilized enzyme preparations with optimized properties. Elucidation, through direct measurement of differences in the internal as compared to the bulk milieu is, therefore, fundamentally important in the mechanistic characterization of immobilized enzymes.

Enzyme performance is influenced by the internal milieu in terms of catalytic rate (“activity”) and stability. The internal milieu for immobilized enzymes is affected by the chemical properties of the solid material and by the interplay of reaction and diffusion. Important differences are in the substrate and product concentration but also in pH and ionic strength.

The liquid milieu in which enzymes operate when they are immobilized in solid materials can be quite different from the milieu in bulk solution.

Kermis simulaties 2d environments