| In this dissertation, a new high biocompatible non-nature amino acid—phenylazophenylalanine (PAP) had been successfully synthesized. The photoisomerizations of PAP was studied by UV-vis spectroscopy, the results suggest that the azobenzene derivatives could be well isomerizesed by light.High quality CdS nanocrystals (CdS QQ) with a narrow size distribution had been successfully synthesized through a reverse micelle route. An observation of transmission electron microscopy (TEM) on the shape of the CdS nanocrystals showed that the nanocrystals were about 5~7nm in size.Then surfaces of CdS Qdots were modified with mercaptoacetic acid (MAA), so that the QD can be dispersed in the water environment since the QD was about to be used as bio probing in the cell biology research. Then PAP was conjugated with the CdS QDs system via condensation reaction between PAP and MAA. The IR spectra confirmed the effect of the surface modification for QDs. Furthermore, we utilized the"Host-Guest"betweenβ-cyclodextrin and azobenzene to embed the QDs and made the QDs system can be controlled by light.Finally, the photocontrolling experiment of the former CdS QD complex structure was conducted. In this experiment, PAP isomerized from cis to trans and excluded fromβ-cyclodextrin, which brought along the QDs getting rid of the restriction ofβ-cyclodextrin. The experiment also confirmed that the QDs were included byβ-cyclodextrin again when the conformation of PAP was changed from trans to cis. In an in vivo experiment with mice, the cytotoxicity of the surface modified CdS QDs was evaluated. The results suggest that the PAP-QDs conjugated withβ-CD rendered nontoxicity, which may further ensured the applications of the QDs system in biological labeling and imaging.
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