![]() Biocatalytic reactions controlling the chemical actuator. Inset: Equivalent logic circuit corresponding to the input-processing biocatalytic cascade. |
Artificial Muscle Reversibly Controlled by
Enzyme Reactions
Chemically induced actuation of a
polypyrrole (Ppy) artificial muscle was controlled by biocatalytic
reactions resulting in the changes of the redox state of the polymer
film mediated by soluble redox species. The biocatalytic process
triggered by diaphorase in the presence of NADH resulting in the
reduction of the Ppy film was reflected by the potential shift in the
negative direction generated in the film. Conversely, the biocatalytic
process driven by laccase in the presence of O2 resulted in
the oxidation of the Ppy film, thus yielding the positive potential
shift. Both reactions produced opposite bending of the Ppy flexible
strip allowing reversible actuation controlled by the biocatalytic
processes. The biocatalytic reactions governing the chemical actuator
can be extended to multi-step cascades processing various patterns of
biochemical signals and mimicking logic networks. The present chemical
actuator exemplifies the first mechano-chemical device controlled by
biochemical means with the possibility to scale up the complexity of
the biochemical signal–processing system.
|
![]() See also movie showing bending of the modified strip upon electrochemical signals. |
![]() The bar chart showing the open circuit
potential changes generated
on the Ppy-strip upon different combinations of the enzyme-input
signals (A,B,C) corresponding to the three-enzyme biocatalytic system.
|