We present a novel theoretical framework within which we are able to design new experimentally realisable materials with tuneable self-assembling properties.

Our work takes inspiration from the results obtained with our recently developed protein coarse graining procedure, namely the “Caterpillar” model [1,2]. Based on these results we postulated the “minimum valence principle" (MVP). According to the MVP in order for a generalised bead-spring system to be designable and foldable, it is sufficient for the chain to have a sequence of different isotropic interactions combined with directional interactions that further constrain the configurational space. Based on this principle we introduced an optimal set of modular sub-units, and the definition of a design procedure necessary to choose a string of the units that once bonded into a chain will spontaneously fold to a specific target structure [3-5].

We show that such structures can be highly non-symmetrical and posses interesting topological properties fully controllable by the sequence of beads along the chain.

Biomimetic patchy polymers represent a considerable step forward in the synthesis of novel materials, because they are based on a limited alphabet of particles that can be reused and assembled, practically, in an infinite number of combinations. Artificial modular self assembling systems such as this one are not available at the moment and the one we propose is the first of this kind.

[1] Coluzza, I. (2011). A coarse-grained approach to protein design: learning from design to understand folding. PloS one, 6(7), e20853. doi:10.1371/journal.pone.0020853

[2] Coluzza, I. (2013). Transferable coarse-grained potential for de novo protein folding and design. Submitted.

[3] Coluzza, I., & Dellago, C. (2012). The configurational space of colloidal patchy polymers with heterogeneous sequences. Journal of Physics: Condensed Matter, 24(28), 284111. doi:10.1088/0953-8984/24/28/284111

[4] Coluzza, I., van Oostrum, P. D. J., Capone, B., Reimhult, E., & Dellago, C. (2012). Design and folding of colloidal patchy polymers. Soft Matter. doi:10.1039/c2sm26967h

[5] Coluzza, I., van Oostrum, P. D. J., Capone, B., Reimhult, E., & Dellago, C. (2013). Sequence Controlled Self-Knotting Colloidal Patchy Polymers. Physical Review Letters, 110(7), 075501. doi:10.1103/PhysRevLett.110.075501