Synthetic polymers present a tremendous number of advanced functionalities – from everyday plastics to highly advanced materials. Many of these polymers are inspired by their natural analogues, the biopolymers such as proteins, DNA or sugars. Nevertheless, synthetic polymers still fail to achieve the same level of complexity of an enzyme or antibody, for example. If we try to understand the differences between the synthetic and biological polymers, it is not about the variety of functional groups that can be introduced into the polymeric chain but rather about the precise positioning of these functional moieties. While biopolymers only use a small library of functional building blocks, e.g. amino acids, they are build up with defined chain length, sequence-defined positioning of the functional groups . Through this sequence-control the overall properties of the polymer are defined including the formation of higher order structures, aggregation behavior, stability and many more properties. Such control is still lacking for synthetic polymers, but, if realized, has great potential to lead to novel materials with superior properties.
Our approach towards monodisperse, sequence-controlled polymers is based on the use of solid phase chemistry. We apply well-established solid phase peptide chemistry but instead of amino acids we use specially designed building blocks or monomers from classical polymer chemistry. Through the iterative coupling of these building blocks on the solid support, we obtain monodisperse and sequence-defined oligo- and polymers.
Special focus is devoted to the synthesis of so-called polymeric biomimetics. These are polymers and polymeric derivatives that mimic the biological properties e.g. of a sugar ligand or peptide motif. In contrast to their natural analogues, polymeric biomimetics often exhibit higher stability, reduced cytotoxicity and immunogenicity and can be more easily synthesized. Through the use of our monodisperse, sequence-controlled macromolecules as polymeric biomimetics in a variety of applications such as sugar- or peptidomimetics in bacteria targeting, we are aiming at an improved design of novel polymeric biomimetics and, more general, a deeper insight into the structure-property correlation of synthetic materials in biology and medicine.