tailieunhanh - Báo cáo hóa học: " One-Pot Synthesis of Biocompatible CdSe/CdS Quantum Dots and Their Applications as Fluorescent Biological Labels"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: One-Pot Synthesis of Biocompatible CdSe/CdS Quantum Dots and Their Applications as Fluorescent Biological Labels | Zhai et al. Nanoscale Res Lett 2011 6 31 http content 6 1 31 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access One-Pot Synthesis of Biocompatible CdSe CdS Quantum Dots and Their Applications as Fluorescent Biological Labels Z-I 71 -1 1 1 1 2 2 P s 1 Chuanxin Zhai Hui Zhang Ning Du Bingdi Chen Hai Huang Yulian Wu Deren Yang Abstract We developed a novel one-pot polyol approach for the synthesis of biocompatible CdSe quantum dots QDs using poly acrylic acid PAA as a capping ligand at 240 C. The morphological and structural characterization confirmed the formation of biocompatible and monodisperse CdSe QDs with several nanometers in size. The encapsulation of CdS thin layers on the surface of CdSe QDs CdSe CdS core-shell QDs was used for passivating the defect emission 650 nm and enhancing the fluorescent quantum yields up to 30 of band-to-band emission 530-600 nm . Moreover the PL emission peak of CdSe CdS core-shell QDs could be tuned from 530 to 600 nm by the size of CdSe core. The as-prepared CdSe CdS core-shell QDs with small size well water solubility good monodispersity and bright PL emission showed high performance as fluorescent cell labels in vitro. The viability of QDs-labeled 293T cells was evaluated using a 3- 4 5-dimethylthiazol -2-diphenyltertrazolium bromide MTT assay. The results showed the satisfactory 80 biocompatibility of as-synthesized PAA-capped QDs at the Cd concentration of 15 gg ml. Introduction Fluorescent semiconductor nanocrystals also known as one kind of quantum dots QDs are of considerable interest and under intensive research as biological labels either in vitro or in vivo not only because of their bright photostable fluorescence but also because of the broad excitation spectrum and narrow size-controlled emission which allows multi-color imaging 1 2 . Among them cadmium selenide CdSe QDs have become one family of the most extensively studied fluorescent semiconductor nanocrystals due