Functional Electrodes Based on Signal-Responsive Materials for Bioelectronic Applications

Chemical systems mimicking Boolean logic gates and their networks are considered as a novel platform for unconventional computing. In most cases, chemical logic operations are activated by external physical or chemical signals, and the readout is read by optical methods or electrochemical means. Normally, the physical nature of the input and output signals is different, making the assembly of multi-component logic networks difficult. They have been applied to model various digital electronic devices. However, the application of biomolecular systems allows achieving higher complexity logic systems while using much simpler chemical tools, due to natural specificity and compatibility of biomolecules.;The thesis outlines different approaches regarding the integration of biocomputing system processing biochemical information and physical signal generating systems with stimuli-responsive polymer functionalized electrode surfaces. Different electrodes modified with signal-responsive materials are designed as switchable electrochemical interfaces controlled by various physical or chemical signals. Besides, "Smart" switchable electrodes for biosensors and biofuel cells with built-in biomolecular logic systems were founded. This work introduces autonomous, individual and "upon-demand" bioelectronic devices by interfacing between the biocomputing systems mimicking biochemical natural network and functional electrodes. Biofuel cells with switchable power release controlled by biomolecular computing systems are presented, and the switchable properties of the biofuel cells are based on the polymer-brush-modified electrodes with the activity dependent on the external pH value. The pH changes generated in situ by bioacatalytic reactions allowed the reversible actuation of the bioelectrocatalytic interfaces, thus affecting the activity of the entire biofuel cells. Integration of switchable electrode interfaces with biocomputing systems based on enzyme- or immune-based systems is evaluated.;In addition, innovative designs of "security" biofuel cells using pH-responsive polymer modified electrodes were integrated with the biocomputing system. An enzyme-based keypad lock system was integrated with a biofuel cell using a pH-switchable cathode as the interface with the electrochemical activity controlled by the "password" encoded in the biomolecular security system. The system allowed self-powered read out of the "answer" generated by the keypad lock system. A further advanced system biomolecular security device included participation of immune-recognition components in the design of the biocomputing logic network.