Enzymes as Biodevelopers for Nano- And Micropatterned Bicomponent Biopolymer Thin Films.

The creation of nano- and micropatterned polymer films is a crucial step for innumerous applications in science and technol. However, there are several problems assocd. with environmental aspects concerning the polymer synthesis itself, crosslinkers to induce the patterns as well as toxic solvents used for the prepn. and even more important development of the films (e.g., chlorobenzene). In this paper, we present a facile method to produce micro- and nanopatterned biopolymer thin films using enzymes as so-called biodevelopers. Instead of synthetic polymers, naturally derived ones are employed, namely, poly-3-hydroxybutyrate and a cellulose deriv., which are dissolved in a common solvent in different ratios and subjected to spin coating. Consequently, the two biopolymers undergo microphase sepn. and different domain sizes are formed depending on the ratio of the biopolymers. The development step proceeds via addn. of the appropriate enzyme (either PHB-depolymerase or cellulase), whereas one of the two biopolymers is selectively degraded, while the other one remains on the surface. In order to highlight the enzymic development of the films, video AFM studies have been performed in real time to image the development process in situ as well as surface plasmon resonance spectroscopy to det. the kinetics. These studies may pave the way for the use of enzymes in patterning processes, particularly for materials intended to be used in a physiol. environment. [on SciFinder(R)]