Proper understanding of viable cell physiology during biocatalytic processes, progress in development of biocompatible immobilization techniques, as well as
introduction of new non-invasive characterization techniques are the main prerequisites for the successful development of novel whole-cell biocatalysts. Selection of the optimal immobilized viable cell biocatalyst is possible when standardised characterization techniques are employed. The development of these techniques requires advanced analytics and a multidisciplinary effort. This
review provides a summary on progress in development of characterization methods and emerging tools for determination of morphology, physiology, and biocatalytic efficiency of immobilized viable whole cells.