FluRox based biosensors

Authors: Nusrat J M Sanghamitra

Publish Date: 2009/04/25

Volume: 8, Issue: 2, Pages: 137-141

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Abstract

A biosensor is an integrated device of biomaterials and electronic components which detects physiological change or physicochemical response The efforts towards the development of a supersensitive FluoRox biosensor are discussed in this paper FluoRox principle is based on the novel concept of monitoring redox events in vitro and in vivo by fluorescence detection based on forster resonance energy transfer FRET Unlike conventional electrochemical biosensors fluorescence based sensors has the advantage of higher sensitivity which under suitable conditions can detect single molecules Thus a highly sensitive and a miniaturized device is aimed at which will enable the detection of trace amounts of pollutants and the detection of diseases at an early stage“Prevention is better than cure” is an age old saying but it rightly acknowledges the challenge that the world is facing today the rapidly growing need of sensitivity in the detection devices or biosensors deployed in various areas like diagnosis of diseases and environmental monitoring of industrial pollutants etc A biosensor is a device that detects records and transmits information regarding a physiological change or the presence of various chemical or biological materials in the environment More technically a biosensor is a probe that integrates a biological component with a physicochemical component to detect an analyteThe Marie Curie Research Training Network EdRox aims at the development of an ultrasensitive biosensor by exploiting the FluoRox principle Unlike typical electrochemical sensors the well known Glucose biosensor Boutelle et al 1996 these FluoRox biosensors implement the novel concept of monitoring redox events in vitro and in vivo by fluorescence detection based on forster resonance energy transfer FRET A leap in sensitivity can be achieved by fluorescence detection which has reached the point of observation of single molecules under suitable conditions Thus it not only has the promise of increasing sensitivity by orders of magnitude but it also allows miniaturization to the submicrometer level thereby opening up new areas of technological applicationsEssentially all life processes are fuelled by redox reactions which is also important in the nonliving world The operating principle of FluoRox biosensors is based on optical detection ie fluorescence intensity ON/OFF of a fluorescently labeled redox protein or enzyme immobilized on an electrode following a redox eventThe FluoRox based method was also explored to detect the substrate binding of cytochrome P450 a heme protein monooxygenase which is an important class of enzyme owing to its diverse reactivity It catalyzes a wide variety of physiologically important processes such as fatty acid metabolism xenobiotic degradation and steroid biosynthesis etc It is also industrially important since it uses a plethora of both exogenous and endogenous compounds as substrates in enzymatic reactions The proof of principle has been provided by the detection of substrate bound and unbound form of cytochrome P450cam which binds to the substrate camphor Since substrate binding is the first step of the catalytic activity it is important to accurately determine the binding affinity of a potential substrate to the enzyme in order to assess its potential for catalytic conversion

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