Trace Oxygen Affects Osmium Redox Polymer Synthesis for Wired Enzymatic Biosensors.

Electrochemical sensors that utilize enzymes are a sensitive, inexpensive means of detecting biologically relevant analytes. These sensors are categorized based on their construction and method of signal transport. Type I sensors consist of a crosslinked enzyme on an electrode surface and are potentially subject to interference from byproducts and other biological analytes.

A low-interference, high-resolution multianalyte electrochemical biosensor.

Electrochemical sensors are used by millions of patients and health care providers every year, yet these measurements are hindered by compounds that also exhibit inherent redox activity. Acetaminophen (APAP) is one such interferent that falls into this extensive class. In this work, an osmium-based redox polymer was used for electrochemical detection in a sensor that was operated at a decreased voltage, allowing for decreased interference.

Polyviologen as Electron Transport Material in Photosystem I-Based Biophotovoltaic Cells.

The photosynthetic protein complex, photosystem I (PSI), can be photoexcited with a quantum efficiency approaching unity and can be integrated into solar energy conversion devices as the photoactive electrode. The incorporation of PSI into conducting polymer frameworks allows for improved conductivity and orientational control in the photoactive layer. Polyviologens are a unique class of organic polycationic polymers that can rapidly accept electrons from a primary donor such as photoexcited PSI and subsequently can donate them to a secondary acceptor.

Construction of a Semiconductor-Biological Interface for Solar Energy Conversion: p-Doped Silicon/Photosystem I/Zinc Oxide.

The interface between photoactive biological materials with two distinct semiconducting electrodes is challenging both to develop and analyze. Building off of our previous work using films of photosystem I (PSI) on p-doped silicon, we have deposited a crystalline zinc oxide (ZnO) anode using confined-plume chemical deposition (CPCD). We demonstrate the ability of CPCD to deposit crystalline ZnO without damage to the PSI biomaterial.

Electrochemical preparation of Photosystem I-polyaniline composite films for biohybrid solar energy conversion.

In this work, we report for the first time the entrapment of the biomolecular supercomplex Photosystem I (PSI) within a conductive polymer network of polyaniline via electrochemical copolymerization. Composite polymer-protein films were prepared on gold electrodes through potentiostatic electropolymerization from a single aqueous solution containing both aniline and PSI. This study demonstrates the controllable integration of large membrane proteins into rapidly prepared composite films, the entrapment of such proteins was observed through photoelectrochemical analysis.

Photoactive films of photosystem I on transparent reduced graphene oxide electrodes.

Photosystem I (PSI) is a photoactive electron-transport protein found in plants that participates in the process of photosynthesis. Because of PSI's abundance in nature and its efficiency with charge transfer and separation, there is a great interest in applying the protein in photoactive electrodes. Here, we developed a completely organic, transparent, conductive electrode using reduced graphene oxide (RGO) on which a multilayer of PSI could be deposited.

Enhanced photocurrents of photosystem I films on p-doped silicon.

Tuning the Fermi energy of silicon through doping leads to alignment of silicon bands with the redox active sites of photosystem I. Integrating photosystem I films with p-doped silicon results in the highest reported photocurrent enhancement for a biohybrid electrode based on photosystem I.