Raman Spectroscopy Cell-based Biosensors

One of the main challenges faced by biodetection systems is the ability to detectand identify a large range of toxins at low concentrations and in short times. Cell-basedbiosensors rely on detecting changes in cell behaviour, metabolism, or induction of celldeath following exposure of live cells to toxic agents. Raman spectroscopy is a powerfultechnique for studying cellular biochemistry. Different toxic chemicals have differenteffects on living cells and induce different time-dependent biochemical changes related tocell death mechanisms. Cellular changes start with membrane receptor signalling leading tocytoplasmic shrinkage and nuclear fragmentation. The potential advantage of Ramanspectroscopy cell-based systems is that they are not engineered to respond specifically to asingle toxic agent but are free to react to many biologically active compounds. Ramanspectroscopy biosensors can also provide additional information from the time-dependentchanges of cellular biochemistry. Since no cell labelling or staining is required, the specifictime dependent biochemical changes in the living cells can be used for the identificationand quantification of the toxic agents. Thus, detection of biochemical changes of cells byRaman spectroscopy could overcome the limitations of other biosensor techniques, withrespect to detection and discrimination of a large range of toxic agents. Furtherdevelopments of this technique may also include integration of cellular microarrays forhigh throughput in vitro toxicological testing of pharmaceuticals and in situ monitoring ofthe growth of engineered tissues.