Field programmable chemistry: Integrated chemical and electronic processing of informational molecules towards electronic chemical cells

• Published in: BioSystems 2012-07, Vol.109 (1), p.2-17
• Main Authors: Wagler, Patrick F., Tangen, Uwe, Maeke, Thomas, McCaskill, John S.
• Format: Article
• Language: English
• Subjects: Artificial cells; Automatic Data Processing - methods; Chemical Engineering - methods; Chemical Engineering - trends; Chemical Phenomena; Computers, Molecular - trends; DNA computing; Electrodes; Electromagnetic Fields; Electrophoresis; Fluorescence; Microcomputers; Microelectrode array; Microfluidic Analytical Techniques; Reconfigurable microfluidics
• ISSN: 0303-2647; 1872-8324
• DOI: 10.1016/j.biosystems.2012.01.005

The topic addressed is that of combining self-constructing chemical systems with electronic computation to form unconventional embedded computation systems performing complex nano-scale chemical tasks autonomously. The hybrid route to complex programmable chemistry, and ultimately to artificial cells based on novel chemistry, requires a solution of the two-way massively parallel coupling problem between digital electronics and chemical systems. We present a chemical microprocessor technology and show how it can provide a generic programmable platform for complex molecular processing tasks in Field Programmable Chemistry, including steps towards the grand challenge of constructing the first electronic chemical cells. Field programmable chemistry employs a massively parallel field of electrodes, under the control of latched voltages, which are used to modulate chemical activity. We implement such a field programmable chemistry which links to chemistry in rather generic, two-phase microfluidic channel networks that are separated into weakly coupled domains. Electric fields, produced by the high-density array of electrodes embedded in the channel floors, are used to control the transport of chemicals across the hydrodynamic barriers separating domains. In the absence of electric fields, separate microfluidic domains are essentially independent with only slow diffusional interchange of chemicals. Electronic chemical cells, based on chemical microprocessors, exploit a spatially resolved sandwich structure in which the electronic and chemical systems are locally coupled through homogeneous fine-grained actuation and sensor networks and play symmetric and complementary roles. We describe how these systems are fabricated, experimentally test their basic functionality, simulate their potential (e.g. for feed forward digital electrophoretic (FFDE) separation) and outline the application to building electronic chemical cells.