METABOLIC MONITORING OF CELLS IN A MICROPLATE READER

摘要

The invention disclosed is a method for monitoring the metabolism of cells retained in individual wells of a multiassay plate by measuring the rates of extracellular acidification comprising the steps of: placing the cells in a solution containing a pH buffer and an acid/base indicator (the acidic form having optimum absorbance in a first wavelength region and the basic form having optimum absorbance in a second wavelength region), heating the solution in the individual wells to a substantially uniform temperature, mixing the solution in each well, measuring the optical densities of light passing vertically through the wells at a first wavelength in the first wavelength region and a second wavelength in the second wavelength region, determining a ratio of the optical density at the first and second wavelengths in each of two, or more wells, and repeating the mixing, measuring, and determining steps to monitor kinetically a rate of change in extracellular pH caused by the cells. The use of selected buffering system-acid/base indicator pairs, which provide little or no optically-apparent change in pH with change in temperature, was found to be highly desirable for carrying out the method. Methods for composing such buffering system-acid/base indicator pairs are disclosed, together with examples of such pairs.