A simple large-volume cell suitable for multiparameter measurements in the aminco-chance spectrophotometer☆☆☆

In order to better understand cellular and subcellular phenomena it is desirable to observe multiple parameters such as pH, various ion movements, optical density at various wavelengths, and kinetics of oxygen consumption. Instrumentation for the measurement of these kinds of parameters has been carefully described by Pressman (11, who used a rectangular cuvet with a plastic covrr fitted with an oxygen electrode, a I(+ electrode and a pH electrode. Fluorescence and light scattering measurements are made with the appropriate light sources and photomultipliers situated at the sides of the cuvet and after proper amplification the signals from these sensors are recorded simultaneously. In this communication we would like to describe a simple cuvet suitable for multiparameter measurements adapted for use with the spectrophotometer designed by Chance (2) and commercially available from the American Instrument Co. as a dual-wavelength split-beam spectrophotometer. Figure 1 shows the essential features of the cell, including the measurements which are critical for the positioning of the cell in the spectrophotometer. Since the cell is patterned after the Bl-65103 cuvet carrier, it fits without modification into the spect’rophotometer just as one would position the cell carriers which come as standard equipment with the instrument. This also ensures that t’he light beam will strike the cuvet properly. The entire cell was made from cast methyl methacrylate except the optical surfaces, viz., t’he two sides of the stirring chamber and one end which is used for fluorescence or light scattering measurements.