Laboratory of Inorganic & Analytical Chemistry, Department of Chemical Sciences, School of Chemical Engineering, National Technical University of Athens, Athens, Greece
Dr. Georgia-Paraskevi Nikoleli
Laboratory of Inorganic & Analytical Chemistry, Department of Chemical Sciences, School of Chemical Engineering, National Technical University of Athens, Athens, Greece
The multifaceted role of biological membranes prompted early the development of artificial lipid-based models with a primary view of reconstituting the natural functions in vitro so as to study and exploit chemoreception for sensor engineering. Over the years, a fair amount of knowledge on the artificial lipid membranes, as both, suspended or supported lipid films and liposomes, has been disseminated and has helped to diversify and expand initial scopes. Artificial lipid membranes can be constructed by several methods, stabilized by various means, functionalized in a variety of ways, experimented upon intensively, and broadly utilized in sensor development, drug testing, drug discovery or as molecular tools and research probes for elucidating the mechanics and the mechanisms of biological membranes. This paper reviews the state-of-the-art, discusses the diversity of applications, and presents future perspectives. The newly-introduced field of artificial cells further broadens the applicability of artificial membranes in studying the evolution of life.
Graphene is one of the new materials which has shown a large impact on the electronic industry due to its versatile properties, such as high specific surface area, high electrical conductivity, chemical stability, and large spectrum of electrochemical properties. The graphene material-based electronic industry has provided flexible devices which are inexpensive, simple and low power-consuming sensor tools, therefore opening an outstanding new door in the field of portable electronic devices. All these attractive advantages of graphene give a platform for the development of a new generation of devices in both food and environmental applications. Lipid-based sensors have proven to be a good route to the construction of novel devices with improved characteristics, such as fast response times, increased sensitivity and selectivity, and the possibility of miniaturization for the construction of portable biosensors. Therefore, the incorporation of a lipid substrate on graphene electrodes has provided a route to the construction of a highly sensitive and selective class of biosensors with fast response times and portability of field applications for the rapid detection of toxicants in the environment and food products.
Proteinaceous moieties are critical elements in most detection systems, including biosensing platforms. Their potential is undoubtedly vast, yet many issues regarding their full exploitation remain unsolved. On the other hand, the biosensor formats with the higher marketability probabilities are enzyme in nature and electrochemical in concept. To no surprise, alternative materials for hosting catalysis within an electrode casing have received much attention lately to demonstrate a catalysis-coated device. Graphene and ZnO are presented as ideal materials to modify electrodes and biosensor platforms, especially in protein-based detection. Our group developed electrochemical sensors based on these nanomaterials for the sensitive detection of cholesterol using cholesterol oxidase incorporated in stabilized lipid films. A comparison between the two platforms is provided and discussed. In a broader sense, the not-so-remote prospect of quickly assembling a protein-based flexible biosensing detector to fulfill site-specific requirements is appealing to both university researchers and industry developers.