Capping biological quantum dots with the peptide CLPFFD to increase stability and to reduce effects on cell viability

  • A. L. Riveros
  • J. Astudillo
  • C. C. Vásquez
  • Danilo H. Jara
  • Ariel R. Guerrero
  • F. Guzman
  • I. O. Osorio-Roman
  • M. J. Kogan
Research Paper


Highly fluorescent nanoparticles, or quantum dots, have multiple applications in biology and biomedicine; however, in most cases, it is necessary to functionalize them to enhance their biocompatibility and selectivity. Generally, functionalization is performed after nanoparticle synthesis and involves the use of molecules or macromolecules having two important traits: specific biological activity and functional groups that facilitate nanoparticle capping (i.e. atom–atom interaction). For this reason, we carried out a simple protocol for the chemical synthesis of cadmium telluride quantum dots capped with glutathione, and we then functionalized these nanoparticles with the amphipathic peptide CLPFFD. This peptide attaches selectively to β-Amyloid fibres, which are involved in Alzheimer’s disease. Our results show that the optical properties of the quantum dots are not affected by functionalization with this peptide. Infrared spectra showed that cadmium telluride quantum dots were functionalized with the peptide CLPFFD. In addition, no significant differences were observed between the surface charge of the quantum dots with or without CLPFFD and the nanocrystal size calculated for HR-TEM was 4.2 nm. Finally, our results show that quantum dots with CLPFFD are stable and that they resulted in a significantly reduced cytotoxicity with respect to that induced by quantum dots not conjugated with the peptide. Moreover, the results show that the CLPFFD-functionalized nanoparticles bind to β-Amyloid fibres.


Cadmium telluride quantum dots β-Amyloid fibres Peptide CLPFFD Cell viability 



Financial support of this paper was provided by the FONDECYT 3130654; Fondap 15130011 and FONDECYT 1130425 Grants.

Supplementary material

11051_2016_3463_MOESM1_ESM.pdf (367 kb)
Supplementary material 1 (PDF 366 kb)


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Copyright information

© Springer Science+Business Media Dordrecht 2016

Authors and Affiliations

  1. 1.Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
  2. 2.Advanced Center for Chronic DiseasesSantiagoChile
  3. 3.Facultad de Química y BiologíaUniversidad de Santiago de ChileSantiagoChile
  4. 4.Radiation Laboratory, Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameUSA
  5. 5.Núcleo de Biotecnología CuraumaPontificia Universidad Católica de ValparaísoValparaisoChile
  6. 6.Department of Chemistry and BiochemistryUniversity of WindsorWindsorCanada

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