Enzymatically Polymerized Organic Conductors on Model Lipid Membranes

Seamless integration between biological systems and electrical components is essential for enabling a twinned biochemical-electrical recording and therapy approach to understand and combat neurological disorders. Employing bioelectronic systems made up of conjugated polymers, which have an innate ability to transport both electronic and ionic charges, provides the possibility of such integration. In particular, translating enzymatically polymerized conductive wires, recently demonstrated in plants and simple organism systems, into mammalian models, is of particular interest for the development of next-generation devices that can monitor and modulate neural signals. As a first step toward achieving this goal, enzyme-mediated polymerization of two thiophene-based monomers is demonstrated on a synthetic lipid bilayer supported on a Au surface. Microgravimetric studies of conducting films polymerized in situ provide insights into their interactions with a lipid bilayer model that mimics the cell membrane. Moreover, the resulting electrical and viscoelastic properties of these self-organizing conducting polymers suggest their potential as materials to form the basis for novel approaches to in vivo neural therapeutics

Voltage measurements from two circuit regimes.

<p>a, closed-circuit regime, i.e., 60 min ~0 kOhm, 10 min 100 kOhm load; a value at the end of the 10 min interval is shown; each replicated measurement run is distinctly colored. b, open circuit, the electrochemical cell is directly connected to the voltmeter, no load; sampling is performed every minute; each replicated measurement run is distinctly colored.</p

Electrochemical cell for investigation of titanium implants.

<p>a, diagram of the cell, b.—actual photograph of the setup, c—electrical schematic diagram.</p

Titanium concentrations measured in the electrochemical cell after 90 h of incubation depending on the circuit regime.

<p>Titanium concentrations measured in the electrochemical cell after 90 h of incubation depending on the circuit regime.</p

Electrochemical cell in a flow-through regime.

<p>A flow of media was established at 0.05 volumes/min through the inoculated (a, two replicates shown) and sterile (b) electrochemical cells.</p

Distribution of measured titanium quantities (log10 scale) recovered from patient samples for the 28 sites.

<p>There were additional 26 sites for which the quantities of titanium fell below the detection limit.</p