Low-oxygen dependent X-photodynamic nano photosensitizer as well as preparation method and application thereof

Abstract

The invention relates to a low-oxygen dependent X-photodynamic nano photosensitizer as well as a preparation method and an application thereof. The low-oxygen dependent X-photodynamic nano photosensitizer comprises nano scintillation crystal particles capable of converting a high-energy radiation ray into an ultraviolet light, a silicon dioxide layer cladded on the surface of the nano scintillation crystal, zinc oxide nanoparticles loaded on the outer surface of the silicon dioxide layer, and polyethylene glycol grafted on the surfaces of the zinc oxide nanoparticles. The nano scintillation crystal capable of converting the high-energy radiation ray into the ultraviolet light is taken as a functional kernel; the nano scintillation crystal can emit a characteristic ultraviolet ray when being irradiated by an X ray; and the characteristic ultraviolet ray can be efficiently absorbed by shell ZnO semiconductor quantum dots, so as to generate electron hole pairs. A lot of high-activity hydroxyl radicals (.OH) and superoxide anions (.O2<->) are generated by complicated physical and chemical reaction, so as to damage cancer cells.

Description

technical field [0001] The invention relates to a hypoxia-dependent X-ray dynamic nano-photosensitizer and its preparation method and application, belonging to the technical field of biomedical nano-materials. Background technique [0002] Malignant tumor is a kind of special disease that seriously threatens human health, and its treatment has attracted more and more attention. Photodynamic therapy (PDT) is an efficient cancer treatment technology that has emerged in recent years. The entire process involves three non-toxic elements, namely light of a specific wavelength (Light), photosensitizer molecules (PS) and oxygen ( o 2 ). The mechanism of action can be briefly described as that light of a specific wavelength activates the photosensitizer to generate cytotoxic reactive oxygen species through complex photochemical and physical processes, thereby selectively killing rapidly proliferating cells. Compared with traditional chemotherapy, radiotherapy and surgery, photody...

AI Technical Summary

Problems solved by technology

Compared with traditional chemotherapy, radiotherapy and surgery, photodynamic therapy (PDT) has been widely studied due to its unique advantages of broad spectrum, flexibility and minimal invasiveness, but its wide application in clinical medicine There are still two key problems in the application: 1) The penetration depth of the excitation light source is shallow: the excitation light of traditional photosensitizers is usually in the ultraviolet-visible light band, and human tissues have strong absorption of light in this band, so there is a living body penetration depth of the excitation light source The shortcoming of low level makes PDT only applicable to superficial skin cancer, which becomes the main obstacle limiting its wide clinical application; 2) High dependence on tissue oxygen partial pressure: studies have shown that the usual PDT process is a type II process, That is, the triplet state of the organic photosensitizer molecule and the ground state oxygen molecule ( 3 o 2 ) undergoes energy transfer to produce cytotoxic singlet oxygen ( 1 o 2 ), as an oxygen consumption process, when the tissue oxygen partial pressure is low, its singlet oxygen production rate is greatly reduced, seriously affecting the therapeutic effect

[0003] Compared with photodynamic therapy, radiotherapy is not limited by the penetration depth of the living body, but it has the defect of low utilization rate of ray energy. In order to achieve the expected therapeutic effect, it is necessary to extend the course of radiotherapy to increase the radiation dose to the tumor area. Inevitably cause strong side effects on the body

Images