Designing instructable networks using synthetic replicators

Synthetic chemistry has focused on the creation of discrete chemical entities through the programmed application of a series of chemical reactions, usually in a linear cascade. By contrast, systems chemistry demands the presence of a mixture of compounds and it is the interactions between these multiple components that are a necessity for the emergence of properties at a whole system level. A key component of systems chemistry will be the development of synthetic machinery that is capable of directing its own synthesis and co-operating with other similar systems to create an organized hierarchy or network. Central to this goal is the development of networks of replicating templates. Although the design and implementation of replicating templates which operate by either autocatalytic or crosscatalytic mechanisms is becoming routine, the incorporation of these templates into networks remains challenging. An initial experimental attempt to create such a network of replicators using a set of replicators previously characterized individually results in an uninstructable system. The failure of this network to respond to template inputs in a programmed manner is rationalized using kinetic simulations and the design criteria necessary to effect a replication network that is capable of responding to template inputs in a programmed way are deduced using kinetic simulations.