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The photoinduced intra-molecular energy transfer in phthalocyanine zinc(II) bearing poly (aryl benzyl ether) dendritic substituents with carboxylic terminal was studied by steady-state, time-resolved fluorescence and UV/Vis spectroscopic methods. The result shows that the complexes mainly existed as monomers in dimethyl sulfoxide. The light-harvesting ability of this series of dendritic phthalocyanines increased with the dendron generation under 270 nm. The effects of the dendron generation on the fluorescence characteristics of phthalocyanine cores was significantly, and the fluorescence lifetime and fluorescent quantum yield decreased with the increase of the dendron generation. Intra-molecular energy could be transferred from peripheral dendron acting as an energy hydrazine to the phthalocyanine core during a photo-induced process. With the dendrimer increasing, the intra-molecular energy transfer quantum yield increased. These results obviously indicated that this series of dendritic phthalocyanines is a king of novel compound with light-harvesting structure.

The tetra-sulfonated phathalocyanine cobalt(CoPcS4)was synthesized by using 4-sulfonic phthalic acid as raw material, CoCl2 as template agent and (NH4)2 MoO4 as catalyst. CoPcS4 was demonstrated to be C4h mono-isomer by elementary analysis, IR, NMR and HLPC. Depolymerization of CoPcS4 was found in DMSO. The depolymerization increased with the pH value raising. The interaction of tetra-sulfonated phathalocyanine cobalt with bovine serum albumin (BSA) was studied by UV-Vis and fluorescence spectra The number of binding sites and binding constant were determined at equal pace of the order of magnitude 10(5) L x mol(-1). CoPcS4 binds with BSA at Site I and Site II. In conclusion, COPcS4 binds with BSA commendably and albumin plays a role of storage and transport.

Octa-carboxylic phthalocyanine aluminium (AlPc(COOH)8) was used as fluorescent probe of infrared region. The interaction of octa-carboxylic phthalocyanine aluminium (AlPc(COOH)s) and bovine serum albumin(BSA) was studied by UV/ Vis and fluorescence spectra methods. The binding constant KA and n of phthalocyanine aluminium with BSA were determined. The results were K=5. 74 X 10(5) , n= 5. 7 and K= 3. 51 X 10(5) , for these two methods respectively. The same results by using two different analytical methods were obtained. Besides, hemin chloride(HE), ibuprofen(IB) and L-tryptophan(TRP) were used as probes, and the effects of these probes on the spectra of AlPc(COOH)8 )-BSA were studied by competitive binding method. The result indicated that, by adding HE into the AlPc(COOH)8)-BSA system, obvious spectral change of the system was observed, while adding TRP and IB caused no spectral changes. The binding site of octa-carboxylic phthalocyanine aluminium on the BSA was found to be at the I site by competitive binding method.

In the present paper, CdS nanoparticles of different size surface-capped with thiourea [expressed as CdS/SC(NH2)2] were prepared by sol-gel method, and characterized by XRD, TEM, IR and PL. The results show that the molar ratio of thiourea to cadmium ion has influence on the size and luminescence properties of the nanoparticles. With increasing the mdar ratio of thiourea to cadmium ion in the reactant, the size of the nanoparticles decreases, and the maximum emission wavelength of the nanoparticles shows an obvious blue shift due to quantum confinement effect. The effect of calf thymus deoxyribonucleic acid (ct-DNA) on the fluorescence spectrum of the CdS/SC(NH2)2 nanoparticles was also studied. The result shows that the intensity of fluorescence spectrum of the nanoparticles is quenched by ct-DNA, which is probably caused by the electrostatic interaction between CdS/SC(NH2)2 nanoparticles and ct-DNA. The CdS/SC(NH2)2 nanoparticles are hopeful of being used as fluorescence probes in DNA determination.