J. M. Roseman, J. Lin, S. Ramakrishnan, J. Rosenstein, and K. L. Shepard, Hybrid integrated biological–solid-state system powered with adenosine triphosphate. Nat. Commun. 6:10070 doi: 10.1038/ncomms10070 (2015).
There is enormous potential in combining the capabilities of the biological and the solid state to create hybrid engineered systems. While there have been recent efforts to harness power from naturally occurring potentials in living systems in plants and animals to power complementary metal-oxide-semiconductor integrated circuits, here we report the first successful effort to isolate the energetics of an electrogenic ion pump in an engineered in vitro environment to power such an artificial system. An integrated circuit is powered by adenosine triphosphate through the action of Na+/K+ adenosine triphosphatases in an integrated in vitro lipid bilayer membrane. The ion pumps (active in the membrane at numbers exceeding 2×106mm-2) are able to sustain a short-circuit current of 32.6 pAmm-2 and an open-circuit voltage of 78mV, providing for a maximum power transfer of 1.27pWmm-2 from a single bilayer. Two series-stacked bilayers provide a voltage sufficient to operate an integrated circuit with a conversion efficiency of chemical to electrical energy of 14.9%.