The Research On Photodynamic And Sonodynamic Therapy By Dyes

Photodynamic therapy is a new treatment model that is minimally invasive,well selective and photo-induced by photosensitisers.Photodynamic therapy with its own unique advantages has become the good selection other than surgery,chemotherapy and radiotherapy treatment.Photodynamic therapy has successfully solved the pain of many patients in the clinical treatment and decreased the recurrence rate of the patients.Sonodynamic therapy has two salient features:high energy and deep penetrability;short wavelength and directional propagation.Because the sonosensitiser can specifically accumulate on the tumor cells and the focus ultrasonic can be selectively irradiated,the surrounding normal tissues suffer less damage.Therefore,sonodynamic therapy has offered a good application prospect.Weak acid in the tumor microenvironment provides a new strategy for cancer treatment.In order to further research of the selective photosensitizer by weak acid tumor microenvironment,we rationally designed a proton-activatable aminated-chrysophanol derivative compound 3 which positioned to the organelles–lysosome.By introducing two tertiary amine substituents the protonated tert-amines can not only excite the photosensitizer but also transfer energy to oxygen and generate a lot of reactive oxygen under weak acid environment.Furthermore,the absorption wavelength of compound 3 redshift and the penetration ability of tissue increase.It produces stronger fluorescence and reactive oxygen species in weakly acidic tumor tissues.In addition,the lysosomal damage experiment also proves that cell necrosis is achieved by destroying lysosomes,and the photosensitizer is expected to provide possibilities for clinical diagnosis and treatment.According to the reported sonosensitizer,the most suitable therapeutic conditions for ultrasonic treatment are found in this paper.And with the testing parameters of the ultrasound we test the Nile blue derivatives which designed by our group.The sonosensitisers introduce the elements of oxygen,sulfur,selenium,tellurium?Nb-O,Nb-S,Nb-Se,Nb–Te?,such as to increase the triplet life of oxygen by heavy atom effect,produce more active oxygen to kill cancer cells.Detected in 1 MHz ultrasonic activation,the Nb-S generates superoxide anion?O₂^-?,Nb-Se produce singlet oxygen?¹O₂?and Nb-Te generate singlet oxygen?¹O₂?.And the Nile blue derivatives are located in RNA of the cell cytoplasm and nucleolus.The cell cytotoxicity is tested by CCK-8 kit and cell apoptosis is tested by flow cytometry.We find that these three derivatives after ultrasound can kill cancer cells.Besides,the novel sonosensitisers are expected to provide for clinical diagnosis and treatment.