Cell imprinting on polymer layers produces synthetic receptors, so called surface imprinted polymers (SIPs) that are suitable for specific and selective cellular recognition. However, their recognition mechanisms are not yet fully understood. Therefore, various factors that influence cell recognition were explored using different spectroscopic techniques. Specifically, the molecular dynamics of surface-imprinted and non-imprinted polyurethane layers was studied with focus on the dielectric relaxation signatures of proteins and lipids by dielectric relaxation spectroscopy. Furthermore, we have tested an interdigitated comb electrode (IDE) structure placed beneath the cell recognition layer. It was shown that both plane and IDE configurations sense the molecular dynamics of the PU layer correctly, and also reveal specific information about the polymer/cell interface.