Enzymes and whole cells are able to catalyze the most complex chemical
processes under the most benign experimental and environmental
conditions. In this way, enzymes and cells could be excellent catalysts
for a much more sustainable chemical industry. However, enzymes and
cells also have some limitations for nonbiological applications: fine
chemistry, food chemistry, analysis, therapeutics, and so on. Enzymes
and cells may be unstable, difficult to handle under nonconventional
conditions, poorly selective toward synthetic substrates, and so forth.
From this point of view, the transformation--from the laboratory to
industry--of chemical processes catalyzed by enzymes and cells may be
one of the most complex and exciting goals in biotechnology. For many
industrial applications, enzymes and cells have to be immobilized, via
very simple and cost-effective protocols, in order to be re-used over
very long periods of time. From this point of view, immobilization,
simplicity, and stabilization have to be strongly related concepts. Over
the last 30 years, a number of protocols for the immobilization of cells
and enzymes have been reported in scientific literature. However, only
very few protocols are simple and useful enough to greatly improve the
functional properties of enzymes and cells, activity, stability,
selectivity, and related properties.
