Controllable synthesis and cell-imaging studies on CdTe quantum dots together capped by glutathione and thioglycolic acid.

This paper describes the synthesis of CdTe quantum dots (QDs) in aqueous solution using two stabilizers (GSH and TGA), which have never been used together but separately. The synthetic procedure is simple and controllable. Different-sized CdTe QDs with controllable photoluminescence (PL) wavelengths from 500 to 610 nm can be synthesized within 5 h in aqueous solutions at a temperature of 100 degrees C. When the molar ratio of GSH to TGA is 1:1, quantum yields (QY) of the yellow-emitting CdTe QD550 (QDs with emission maximum at 550 nm) obtained can reach to 63% without any postpreparation treatment. The synthesized CdTe QDs possess free carboxyl and amino groups, which were successfully conjugated with insulin (INS) for delivery to cells, demonstrating that they can be easily bound bimolecularly and have potentially broad applications as bioprobes.

[1]  Bai Yang,et al.  NHS-mediated QDs-peptide/protein conjugation and its application for cell labeling. , 2008, Talanta.

[2]  Xiaogang Peng,et al.  Experimental Determination of the Extinction Coefficient of CdTe, CdSe, and CdS Nanocrystals , 2003 .

[3]  Nikolai Gaponik,et al.  THIOL-CAPPING OF CDTE NANOCRYSTALS: AN ALTERNATIVE TO ORGANOMETALLIC SYNTHETIC ROUTES , 2002 .

[4]  Lei Zhang,et al.  Novel Strategy for Synthesis of High Quality CdTe Nanocrystals in Aqueous Solution , 2008 .

[5]  G. Müller,et al.  Adjustment of the Band Gap Energies of Biostabilized CdS Nanoparticles by Application of Statistical Design of Experiments , 2004 .

[6]  Q. Ma,et al.  Synthesis of CdTe nanocrystals with mercaptosuccinic acid as stabilizer. , 2008, Journal of nanoscience and nanotechnology.

[7]  Tobias Vossmeyer,et al.  CdS Nanoclusters: Synthesis, Characterization, Size Dependent Oscillator Strength, Temperature Shift of the Excitonic Transition Energy, and Reversible Absorbance Shift , 1994 .

[8]  J. Ying,et al.  Synthesis and Cell‐Imaging Applications of Glutathione‐Capped CdTe Quantum Dots , 2007 .

[9]  N. Murase,et al.  SYNTHESIS AND OPTICAL PROPERTIES OF WATER SOLUBLE ZnSe NANOCRYSTALS , 2001 .

[10]  S. Nie,et al.  In vivo cancer targeting and imaging with semiconductor quantum dots , 2004, Nature Biotechnology.

[11]  Alf Mews,et al.  Synthesis and characterization of highly luminescent CdSe-core CdS/Zn0.5Cd0.5S/ZnS multishell nanocrystals. , 2005, Journal of the American Chemical Society.

[12]  A. Rogach,et al.  Synthesis and Characterization of a Size Series of Extremely Small Thiol-Stabilized CdSe Nanocrystals , 1999 .

[13]  M. Bawendi,et al.  Synthesis and characterization of nearly monodisperse CdE (E = sulfur, selenium, tellurium) semiconductor nanocrystallites , 1993 .

[14]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[15]  E. Grill,et al.  Phytochelatins: The Principal Heavy-Metal Complexing Peptides of Higher Plants , 1985, Science.

[16]  S. Gambhir,et al.  Quantum Dots for Live Cells, in Vivo Imaging, and Diagnostics , 2005, Science.

[17]  H. Schägger.  Tricine–SDS-PAGE , 2006, Nature Protocols.

[18]  Xiaogang Peng,et al.  Formation of high-quality CdTe, CdSe, and CdS nanocrystals using CdO as precursor. , 2001, Journal of the American Chemical Society.

[19]  Huifeng Qian,et al.  Facile one-pot synthesis of luminescent, water-soluble, and biocompatible glutathione-coated CdTe nanocrystals. , 2006, Small.

[20]  Mingyuan Gao,et al.  The Influence of Carboxyl Groups on the Photoluminescence of Mercaptocarboxylic Acid-Stabilized CdTe Nanoparticles , 2003 .

[21]  Hao Zhang,et al.  Preparation of Luminescent Polyelectrolyte/Cu-Doped ZnSe Nanoparticle Multilayer Composite Films. , 2001, Journal of colloid and interface science.

[22]  H. Gasteiger,et al.  Structure and Chemical Composition of a Supported Pt-Ru Electrocatalyst for Methanol Oxidation , 1995 .

[23]  Wolfgang Knoll,et al.  Composition-tunable Zn(x)Cd(1-x)Se nanocrystals with high luminescence and stability. , 2003, Journal of the American Chemical Society.

[24]  J. Demas,et al.  Measurement of photoluminescence quantum yields. Review , 1971 .

[25]  S. Nie,et al.  Quantum dot bioconjugates for ultrasensitive nonisotopic detection. , 1998, Science.