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The conducting polymer poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT-PSS) was patterned by micromolding in capillaries (MIMIC), in the form of nanowires on a glass or a Si wafer. The periods of the molded nanowires were 833 or 278 nm. By applying force on top of the stamp during MIMIC, the height of these nanowires could be changed. An alternative method of preparing structured surfaces is the liquid embossing technique, used to pattern polymers deposited from dispersion. Nanowires (278 nm) and 2-D nanodots on semiconducting polymer (poly(3-(2‘-methoxy-5‘-octyphenyl) thiophene)) POMeOPT were also achieved by another soft lithography techniquesoft-embossing. The possibility to pattern both semiconducting and metallic conjugated polymers from aqueous solutions or organic solvents on a submicron level makes it possible to use these materials in flexible optoelectronic devices where light propagation and electronic paths are defined by patterning.

This study presents experiments designed to study the stability of the conducting polymer poly(3,4-ethylene dioxythiophene) (PEDOT), under simulated physiological conditions using phosphate-buffered saline (PBS) and hydrogen peroxide (H(2)O(2)) (0.01 M) at 37 degrees C over a 5- to 6-week period. Voltage pulsing in PBS was used as an additional test environment. The influence of switching the counter ion used in electropolymerization from polystyrene sulphonate (PSS) to heparin was investigated. Absorbance spectroscopy and cyclic voltammetry were used to evaluate the material properties. Most of the samples in H(2)O(2) lost both electroactivity and optical absorbance within the study period, but PEDOT:PSS was found slightly more stable than PEDOT:heparin. Polymers were relatively stable in PBS throughout the study period, with around 80% of electroactivity remaining after 5 weeks, disregarding delamination, which was a significant problem especially for polymer on indium tin oxide substrates. Voltage pulsing in PBS did not increase degradation. The counter ion influenced the time course of degradation in oxidizing agents.

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