OPTICAL BIOSENSORS BASED ON FISH PIGMENT-CELLS

Melanophores (black pigment cells) in isolated fish scales have the ability to either aggregate their intracellular pigment granules to the centre or disperse them throughout the cell. Noradrenaline stimulates aggregation within these cells. The sensitivity to noradrenaline is considerably increased after approximately one week of isolation of the scales in a tissue culture medium. In order to measure simultaneously pigment aggregation in several isolated scales, a multichannel fibre-optic system has been developed. The system enables the scales to be constantly perfused with tissue culture medium, which in turn allows measurements to be made over long periods of time. After nine days of isolation there is an approximately 12 000-fold increase in noradrenaline sensitivity. The fibre-optic system, combined with cultured melanophores and molecular biology techniques, should provide a number of interesting biosensing possibilities.