Use of charge coupled device camera for imaging of intracellular phthalocyanines

A highly sensitive charge-coupled device (CCD) camera, linked to a computerized image processor, has been used to obtain fluorescence images of chloro-aluminum sulfonated phthalocyanine (ClAlSPc), and its mono- to tetra-sulfonated constituents, in cells recovered from the peritoneal cavity of dye-treated mice. Immunofluorescence and cytochemistry showed that cells which preferentially took up ClAlSPc and its sulfonated species were predominantly of the monocyte-macrophage series. While this technique may be of use in determining the nature of those cells capable of taking up light sensitive dyes and, perhaps, the intracellular location of such agents, the possibility that photoinactivation by dye aggregation could reduce the sensitivity of this procedure is discussed.