Radical polymerization inside living cells

Polymerisation reactions conducted inside cells must be compatible with the complex intracellular environment, which contains numerous molecules and functional groups that could potentially prevent or quench polymerisation reactions. Here we report a strategy for directly synthesising unnatural polymers in cells through free radical photo-polymerisation using a number of biocompatible acrylic and methacrylic monomers. This offers a platform to manipulate, track and control cellular behaviour by the in cellulo generation of macromolecules that have the ability to alter cellular motility, label cells by the generation of fluorescent polymers for long-term tracking studies, as well as the generation within cells of a variety of nanostructures. It is remarkable that free radical polymerisation chemistry can take place within such complex cellular environments and this demonstration opens up a multitude of new possibilities for how chemists can modulate cellular function and behaviour and for understanding cellular behaviour in response to the generation of free radicals.