Experimental Research on the Photobleaching Mechanism of PDT Based QDs-CdSe *

With the development of the basic research of photodynamic therapy (PDT), photosensitizer photobleaching has become a highly focused area of research within PDT in recent years. In this paper, the photobleaching mechanism of quantum dots in the FBS solution and HL60 cell solutions with oxygen substrate were investigated by the method of theoretical derivation. The results demonstrated that the photobleaching in the single solution was corresponded with the first order kinetics while the photobleaching in the complex solution was corresponded with the second order kinetics. The curve and rate of CdSe photobleaching were obtained by determining the vis absorption spectrum of the CdSe and using of the Beer. Additionally, the photobleaching properties of quantum dot (CdSe) whose theoretical derivation can be confirmed by our experiment were gained.