The PACE project attempts to establish a novel kind of IT-intensive chemical integration technology. This is different in scope and rationale from the now quite well-establishedlab-on-a-chiptechnology - with its focus on analytical functionality.
Rather we address the issue of spatially regulating chemical reactions to foster their integration into functional units: for which the artificial cell provides a major target. The key idea is to complement what chemists can now achieve with the aid of a programmable fine-grained microscopic physical system. In order to fulfill this role, the system must not only be composed of both sensory and actuation systems (as in a lab-on-a-chip), but support microscopic feedback loops that directly link the sensors with actuators at the space and timescale relevant to emergent single chemical cell function. We demonstrate how this is possible making use of electrical reconfigurable microcircuitry. Once this is achieved then a route to artificial cells is open via hybrid entities containing both chemical and microsystemic feedback loops. So the emphasis in PACE is on constructing programmable physical feedback loops that can interact with chemical processes to augment the fucntioning and programmability of chemical systems as they approach full artificial cell functionality. Work in this section involves developing the technology and machinery required to meet these goals, and testing its operation in connection with spatial confinement and the autonomous chemical reactions being developed in the project. The vision can be extended to include artificial chemical cells that have an electronic genome, since chemical closure including replication is one of the hardest tasks that chemical integration has to achieve to design an artificial cell. The role of microfluidics in the PACE project is thus much more that of defining intelligent microenvironments for chemical integration than the conventional one of providing high throughput assay technology. The relation of this technolgy to evolutionary optimization is addressed in the next section. The main thems addressed here are: