Prof. Helmut Schlaad "Functional polymers from amino acids and sugars"

Biological (renewable) building blocks, especially amino acids and sugars, are used to prepare well-defined functional polymers, for instance stimuli-responsive (smart) glycopolypeptides and polypeptide hydrogels.

Statistical copolypeptides based on allylglycine and γ-benzyl-L-glutamate were prepared by ring-opening copolymerization of corresponding N-carboxyanhydrides. The allylglycine units were “click” functionalized with 2,3,4,6-tetra-O-acetyl-1-thio-β-D-glucopyranose applying thiol-ene photochemistry. Subsequent removal of the acetyl and benzyl protecting groups yielded glycosylated poly(L-glutamate)s, which were capable of recognizing proteins (specific carbohydrate-lectin interactions) and changing solution properties (ionization and conformation) in dependence of solution pH.

Poly(γ-benzyl-L-glutamate-co-allylglycine) formed organogels at < 2% w/v in toluene, tetrahydrofuran, or 1,4-dioxane, assisted by UV-crosslinking with dithiol. Debenzylation of dioxane gels yielded and highly absorbent and pH-responsive poly(L-glutamate) hydrogels, which are attractive materials for biomedical applications.
 

 invited by Günter Reiter