F222 Development of a real-time measurement device for concentration of the aqueous solution to a perfusion microscope

An optical densitometer was developed to monitor the change of solute concentration of the solution supplied to a perfusion microscope, which has been developed to observe osmotic response of cells. The concentration of a solution that was supplied to a channel with a 0.5 × 0.5 mm^2 square cross section was determined from the position of a laser beam that passed through the channel, utilizing the change in the refractive index with the concentration of the solution. Real-time measurement of the concentration change was demonstrated with the device installed in the perfusion microscope for several patterns of concentration change.