The photological function of MPA coated CdTe QDs and their biocompatibility / 细胞与分子免疫学杂志

ABSTRACT

AIM: To investigate the CdTe quantum dots coated with MPA and explore its biocompatibility with living cells. METHODS: CdTe quantum dots coated with MPA were prepared in aqueous phase and MPA CdTe QDs were Characterized with TEM, fluorospectrophotometer and ultraviolet spectrophotometer. QDs were Modified with with avidin, purified and prepared as flurescent probe. LSCM was used to observe the expression of MHC Ⅱ antigen on PMφ cells, which was labeled by QDs. Cell culture and MTT assays were used to determine the biocompatibility of MPA coated CdTe quantum dots with the B-16 cells as target cells. RESULTS: The particle diameter of CdTe quantum dots prepared in aqueous phase was well distributed. They had good photological performance and greater stability after coated with MPA. MHC Ⅱ antigen on PMφ was labeled with the QDs-Avidin fluorescent probe showed great fluorescence intensity, which was easy to be detected by fluorescence microscope and LSCM. MPA CdTe QDs showed cytotoxicity when its density was very high, but they showed little cytotoxicity during the normal use of influence label density limit. CONCLUSION: MPA CdTe QDs can be used as new fluorescent lable as they are of even size, not easy to bleach or quench, have good photological performance and stability and good biocompatibility.