An imaging study and spectroscopic curing analysis on polymers for synthetic whole-cell receptors for bacterial detection

Surface imprinted polymers (SIPs) are versatile receptors in bioanalytical applications for the selective detection of cells and microorganisms such as bacteria. One of the synthesis routes is the so-called stamping method in which template bacteria are pressed mechanically into a thin, gel-like polyurethane layer, which is then cured in the presence of the templates to create cell-specific binding pockets on the polymer. The present work focusses on two specific steps of the imprinting protocol: first, we evaluate the sedimentation of two different groups of bacteria, Escherichia coli and Escherichia blattae, on silicone stamps with respect to the resulting surface coverage, which is a key factor for the efficiency of the imprinting process. Second, we analyse the temperature dependence of the thermal- and dielectric properties of polyurethane during curing by dielectric- and pyroelectric spectroscopy. This provides information for improved curing protocols and on the stability of SIP materials at elevated temperatures.