Biological Trace Element Research

, Volume 146, Issue 3, pp 396–401 | Cite as

The Interactions of Glutathione-Capped CdTe Quantum Dots with Trypsin

  • Bingjun Yang
  • Rutao Liu
  • Xiaopeng Hao
  • Yongzhong Wu
  • Jie Du


Due to their unique fluorescent properties, quantum dots present a great potential for biolabelling applications; however, the toxic interactions of quantum dots with biopolymers are little known. The toxic interactions of glutathione-capped CdTe quantum dots with trypsin were studied in this paper using synchronous fluorescence spectroscopy, fluorescence emission spectra, and UV–vis absorption spectra. The interaction between CdTe quantum dots and trypsin resulted in structure changes of trypsin and inhibited trypsin's activity. Fluorescence emission spectra revealed that the quenching mechanism of trypsin by CdTe quantum dots was a static quenching process. The binding constant and the number of binding sites at 288 and 298 K were calculated to be 1.98 × 106 L mol−1 and 1.37, and 6.43 × 104 L mol−1 and 1.09, respectively. Hydrogen bonds and van der Waals' forces played major roles in this process.


Quantum dots Trypsin Toxic interaction Multi-spectroscopic techniques Fluorescence spectroscopy 


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Bingjun Yang
    • 1
  • Rutao Liu
    • 1
  • Xiaopeng Hao
    • 2
  • Yongzhong Wu
    • 2
  • Jie Du
    • 2
  1. 1.Shandong Key Laboratory of Water Pollution Control and Resource ReuseSchool of Environmental Science and Engineering Shandong University, China–America CRC for Environment & HealthJinanPeople’s Republic of China
  2. 2.State Key Laboratory of Crystal MaterialsShandong UniversityJinanPeople’s Republic of China

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