Design Of Novel Photosensitizers Based On BODIPY And Their Application In Photodynamic Therapy

Photodynamic therapy(PDT)is a promising treatment for cancer due to its low systematic toxicity,minimal invasiveness,little drug resistance and so on.One of the important elements for PDT is the choose of photosensitizers.Fluoroboryl dipyrrole compounds(BODIPY)and their derivatives possess excellent optical properties,such as high molar extinction coefficient and good light stability.However,the poor solubility in water limits their development in biomedical fields.Therefore,BODIPY can be used as photosensitizers for effective PDT once it can be taken up by cells.In this issues,BODIPY was prepared as nanoparticles,BODIPY contained porous organic polymers(POP)and metal organic frames(MOF)were integrated into one system.These two methods achieve the endocytosis of BODIPY-based photosensitizer and exhibit well therapeutic effect.The main works are as following:1.A BODIPY dimer(DBDP)was self-assembled to form stable nanoparticles(DBDP NPs),possessing excellent water solubility.Experiments showed that DBDP NPs have pretty small diamater and can be endocytosed by cells effectively.The nanoparticals can generate singlet oxygen to kill cancer cells after being excited by light,achieving effective photodynamic therapy.2.A BDP-POP-MOF nanocomposite(UBP)based on BODIPY was designed and synthesized.The UBP nanocomposites were prepared via template strategy,solving the shortcoming of POP,such as easy to aggregate and poor dispersibility in aqueous solutions.Experiments showed that UBP has good dispersion in aqueous solution and can be effectively endocytosed by cells.After being irradiated with light,the UBP can generate hydroxyl radicals to kill tumor cells through an oxygen-independent type I mechanism.At the same time,the pH-responsive properties enable it to achieve selective treatment for tumor cells and normal cells.