Molecular Bio-Sensors and the Biological and Biomedical Activities of Vanadium

234Vanadium is one of the ten first-row transition metals that is generally not recognized as an essential element in humans but is essential in other organisms, such as some tunicates, algae, and worms. Because vanadium has both beneficial biological effects to humans and the biosphere in general as well as toxic effects, more knowledge about vanadium’s mechanism of actions in either positive or negative ways remains important. Uncovering fundamental mechanisms for observed activities of vanadium is complicated by vanadium’s ability to interact and form complexes with both anions and cations as well as complex speciation chemistry. Since speciation is important to the effects of vanadium, studies about vanadium have depended, and will continue to depend, on the ability to measure vanadium content in vanadium-containing systems and to evaluate the speciation of this vanadium content. Vanadium has also proved useful in the development of sensors that include effective devices based on a combination of enzymatic and electrochemical detection. The integration of vanadium oxides into sophisticated bio-sensors, particularly for environmental, biological, and biomedical samples, also involves a variety of systems that take advantage of, mainly, vanadium oxide’s desirable electrochemical properties. The widespread use of such vanadium-containing systems documents the impact of vanadium chemistry on a range of important medical and societal problems.