Modification of CdTe quantum dots as temperature-insensitive bioprobes.
CdTe quantum dots (QDs) were synthesized in aqueous solution with 3-mercaptopropionic acid (MPA) as the stabilizer. The photoluminescence (PL) of CdTe QDs (3.5nm) is found to be temperature-dependent: as the temperature arising from 278K to 323K, the PL intensity declines to 50.2% of its original and PL emission peak shows obvious red-shift ( approximately 7nm). After modification of the QDs surface with denatured ovalbumin, the PL is more temperature-insensitive than before. The PL intensity retains more than 70% of its original and the emission peak shows less red-shift ( approximately 2nm). Moreover, it is found that the PL intensity and wavelength of denatured ovalbumin coated CdTe QDs are reversible during heating (323K)-cooling (278K) cycles. All the studies provide an important theoretical basis for searching temperature-insensitive bioprobes.
Wang
Jian-Hao
JH
Key Laboratory of Biomedical Photonics of Ministry of Education, Wuhan National Laboratory for Optoelectronics, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, HuBei, PR China, 430074.
Wang
Hai-Qiao
HQ
Li
Yong-Qiang
YQ
Zhang
Hai-Li
HL
Li
Xiu-Qing
XQ
Hua
Xiao-Feng
XF
Cao
Yuan-Cheng
YC
Huang
Zhen-Li
ZL
Zhao
Yuan-Di
YD
D002104:Cadmium / Q000737:chemistry*; D049449:Luminescence; D015335:Molecular Probes; D045663:Quantum Dots; D013691:Tellurium / Q000737:chemistry*; D013696:Temperature
D015335:Molecular Probes; D002104:Cadmium; D013691:Tellurium