Distribution, Trafficking, and in Vitro Photodynamic Therapy Efficacy of Cholesterol Silicon(IV) Phthalocyanine and Its Nanoparticles in Breast Cancer Cells.

A cholesterol silicon(IV) phthalocyanine (Chol-Pc) and a water-soluble Chol-Pc based nanoparticle (DSPE@Chol-Pc), which was prepared using 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(poly(ethylene glycol))-2000] (DSPE-PEG2000) as a nanocarrier were developed. Chol-Pc readily distributed within the cholesterol-rich domains and was preferentially localized in the Golgi apparatus after being transported into the cells. The trafficking of DSPE@Chol-Pc in breast cancer cells was visualized by tracking the fluorescence of Chol-Pc and FITC-labeled DSPE-PEG2000 through two-photonic imaging in real-time. It was discovered that Chol-Pc disassociated from the DSPE-PEG2000 on the plasma membrane and traveled to the cholesterol-rich domains soon afterward. Both DSPE@Chol-Pc and Chol-Pc effectively mediated photodynamic therapy to kill the breast cancer cells. After light irradiation, we found that the organizations of clustered cholesterol-rich domains in cells were destroyed, presumably leading to the death of cells for photodynamic therapy. It should be noted that DSPE@Chol-Pc is highly soluble in aqueous solution and has strong red fluorescence under two-photon excitation. Thus, it could be an excellent probe for detecting cholesterol-rich domains and studying transport processes of cholesterol in living cells.

A polyfluoroalkyl substituted phthalocyanine based supramolecular light switch for photothermal and photodynamic antibacterial activity against Escherichia coli.

A polyfluoroalkyl substituted phthalocyanine based supramolecular light switch was assembled by the host-guest interaction between the novel polyfluoroalkyl substituted silicon phthalocyanine and pyrene-ß-cyclodextrin, which was attached on the sidewalls of SWNTs through the pyrene groups. This supermolecule can not only absorb light to convert its energy into heat energy, but also respond to light, control the release of phthalocyanine and restore fluorescence and produce singlet oxygen for a synergistic photothermal and photodynamic effect against Escherichia coli.

Morpholinyl dendrimer phthalocyanine: synthesis, photophysical properties and photoinduced intramolecular electron transfer.

In this work, a novel series of morpholinyl dendrimer phthalocyanines were synthesized. Their structures were characterized by 1H NMR, IR, elemental analysis, ESI-MS as well as MALDI-TOF MS. The photophysical properties of these phthalocyanines were studied by UV/Vis and fluorescence spectroscopic methods. The photophysical properties of these dendrimer phthalocyanines exhibited dependence on the number of morpholinyl groups and the central ion. The photoinduced intramolecular electron transfer from the morpholinyl groups to the phthalocyanine ring was evidenced by the remarkably quenched fluorescence intensity and shortened lifetime of the silicon phthalocyanine. This difference in photoinduced intramolecular electron transfer effect for axially and peripherally substituted morpholinyl dendrimer phthalocyanines was also studied. Besides, introduction of morpholinyl groups on the dendrimer structure could enhance water solubility as well as increase the singlet oxygen quantum yield.