Protein-based catalysis
Until the discovery of ATRP, polymer chemists were limited in their ability to control the composition and architecture of macromolecules. In 1995, Carnegie Mellon University Professor Krzysztof Matyjaszewski discovered one of the first CRP methods: copper-mediated ATRP. This technique allows synthesis of fundamentally new materials with complex, well-defined nano-scale architectures.ATRP differs from earlier conventional radical-based polymer manufacturing methods by allowing production of complex polymer structures using a catalyst that adds one or a few monomers at a time to a growing polymer chain. Polymers prepared by ATRP find applications in nanotechnology, biomedicine and advanced materials.However conventional ATRP catalysts are based on complexes of transition metals and have some drawbacks as they can be toxic and difficult to remove from the polymeric product. Moreover, they can interfere with the polymer's intended applications. The Marie Curie 'Protein-based ATRP catalysts: From nanoreactors to ATRPases' (PROTEINATRP) grant investigated the possibility of enhancing performance of conventional ATRP catalysts, as well as replacing them with environmentally benign ones.Protein–catalyst conjugates provide an efficient way of removing the copper catalyst quantitatively from the polymer product. While working on protein–catalyst conjugates, project members discovered that some native, non-modified proteins can catalyse ATRP. The ATRPase activity of the enzyme horseradish peroxidase and the protein haemoglobin was investigated in great detail. The polymerisations followed first-order kinetics and the proteins were stable under the reaction conditions, as evidenced by a multitude of analytical methods.This grant support led to the discovery of new ATRP catalysts, and supports further academic research on the subject.
