Electrochemical deposition of highly hydrophobic perfluorinated polyaniline film for biosensor applications

Highly hydrophobic perfluorinated polyaniline thin films with water contact angle of similar to 140 degrees and low internal resistance properties are prepared through electrochemical polymerization. UV-visible spectroscopy demonstrates a gradual evolution of the polaron band which indicates the electronic conductive properties of the polymers. Simultaneous possession of the water-repelling property and electron conductivity for superhydrophobic perfluorinated polyaniline leads to a unique polymer that is suitable as a solid contact in ion-selective electrodes for in situ monitoring of pH changes during early stages of inflammation and septic shock. The superhydrophobic properties should suppress interactions with interfering salts and proteins, and the sensitivity towards protons could be monitored by measuring the phase boundary potential, which depends on the H+ concentration. The potentiometric measurements demonstrate a fast response with a slope of 44.4 +/- 0.2 mV per unit pH. The presence of interfering ions and/or human serum albumin does not have any significant effect on the performance of the perfluorinated film. Moreover, it is demonstrated that the response of the perfluorinated film is reversible within the biomedically relevant pH range from 4.0 to 8.5, and stable over time.

Automated summary

Highly hydrophobic perfluorinated polyaniline thin films were successfully prepared through electrochemical polymerization with excellent electronic conductivity and water-repelling properties. These films can serve as solid contacts for in situ monitoring of pH changes during early stages of inflammation and septic shock, demonstrating a fast response and stability over time. The superhydrophobic nature of the films allows suppression of interactions with interfering salts and proteins, making them suitable for biomedical applications.