Preparation And Photosensitive Properties Studies Of Hydrophilic Non-aggregate Phthalocyanine@SiO₂ Particles

Among all of disease threatened human’s life and health, cancer is one of chief culprits. In biomedical field, there are many kinds of cancer treatment. Compared with the traditional treatments of cancer, photodynamic therapy (PDT) has been getting a lot of attention as a new alternative, for its advantages during treatment. When silica nanoparticles is used as the drug carriers during PDT process, it is beneficial to improve the effective delivery of drug. In the presented thesis, the selected hydrophobic phthalocyanine photosensitizer was attempted to be encapsulated into silicon nanoparticles. And their physical and chemical properties were studied. By this way, the low solubility and high aggregation tendency of phthalocyanine in aqueous solution are both improved. In addition, these obtained nanoparticles had also been studied as photosensitizer for photoinduction oxidization of phenol, a common organic pollutant.The first chapter was introduction. The development, principle and advantages of PDT were reviewed. Meanwhile, several important drug nanocarriers were introduced, the advantage of silica nanoparticles (SiO2 NP) as drug carrier and the prospect of their applications in clinical was especially emphasised. Finally, the current development of phthalocyanine photosensitizer was reviewed. Based on this, the selected topic basis and research content of this paper were presented.In Chapter 2, preparation and characterization of ZnPc(OAr)4@SiO2 NP were reported. The ZnPc(OAr)4@SiO2 NP of 100 run size were prepared using the micro-emulsion method. It was showed from TEM that the NPs were highly dispersed and uniform in particle size distribution. The singlet oxygen yield of ZnPc(OAr)4@SiO2 NPs in DMF was 0.66 determined by chemiluminescence method. Based on the photoinduced chemiluminescence (PCL) effect of ZnPc(OAr)4@SiO2, a type of adapter sensor was designed to detect thrombin. The result showed that the limit of detection was low to 25 pM. The experiment resulted confirmed that this sensor had high selectivity.In Chapter 3, the PDT activity of ZnPc(OAr)4@SiO2 was researched. The surface of ZnPc(OAr)4@SiO2 NP was modified with folic acid (FA) by cross-linking reaction. The absorption spectrum in DMF showed no significant difference between the FA modified NPs and the unmodified ones. When the final concentration of phthalocyanine was both 2.1 μM, the survival rate of MDA-MB-231 cancer cells was 60.2%,51.2% and 49.2%, respectively after ZnPc(OAr)4, ZnPc(OAr)4@SiO2 and ZnPc(OAr)4@SiO2-FA PDT.In Chapter 4, ZnPc(OAr)4@SiO2 NPs were ultized to induce phenol changing for being oxidated. During experiments, the selected light source was high pressure mercury lamp with Visible Light (γ> 550 nm) Filter. The result showed that ZnPc(OAr)4@SiO2 NPs could work as photochemical oxidants for the change of phenol by using singlet oxygen generated. And, the rate constant of process was 9.16 ×10-3min-1.