ALUMINUM PHTHALOCYANINE TETRASULFONATE IN MCF-10F, HUMAN BREAST EPITHELIAL-CELLS - A HOLE-BURNING STUDY

Laser-induced holes are burned in the absorption spectrum of aluminum phthalocyanine tetrasulfonate (APT) in MCF-10F, human breast epithelia l cells. The hole burning mechanism is shown to be nonphotochemical. T he fluorescence excitation spectra and hole spectra are compared with those of APT in hyperquenched glassy films of water, ethanol, and meth anol. The results show that the APT is in an acidic, aqueous environme nt with a hydrogen-bonded network similar to that of glassy water, but showing the influence of other cellular components. Pressure shifts o f holes allow the local compressibility about the APT to be determined .