Analytical and Bioanalytical Chemistry

, Volume 400, Issue 2, pp 483–492 | Cite as

Supramolecular complexes of quantum dots and a polyamidoamine (PAMAM)-folate derivative for molecular imaging of cancer cells

  • Daniela A. Geraldo
  • Esteban F. Duran-Lara
  • Daniel Aguayo
  • Raul E. Cachau
  • Jaime Tapia
  • Rodrigo Esparza
  • Miguel J. Yacaman
  • Fernando Danilo Gonzalez-Nilo
  • Leonardo S. SantosEmail author
Original Paper


Polyamidoamine (PAMAM) dendrimers and water-soluble 3-mercaptopropionic acid (MPA)-capped CdSe quantum dots (QDs) were combined to produce a new gel containing supramolecular complexes of QDs/PAMAM dendrimers. The formation of the QDs/PAMAM supramolecular complexes was confirmed by high resolution electron microscopy and Fourier transform infrared (FTIR) analyses. Molecular dynamics simulations corroborated the structure of the new QDs/PAMAM-based supramolecular compound. Finally, on the basis of the prominent fluorescent properties of the supramolecular complexes, PAMAM dendrimer was functionalized with folic acid to produce a new QDs/PAMAM-folate derivative that showed an efficient and selective performance as a marker for gastric cancer cells.


The new QDs/PAMAM-folate derivative (left) is a selective marker for imaging of cancer cells as illustrated by the fluorescence image of human stomach adenocarcinoma (AGS) cells with internalized marker (right)


Quantum dots PAMAM dendrimers Supramolecular complexes Transmission electron microscopy (TEM) Molecular dynamics (MD) simulations Gastric cancer cells 



D.A.G. and L.S.S. thank FONDECYT (Postdoctoral Grant 3100037), Proyecto Anillo Científico ACT/24 (F.D.G.N.), and University of Texas at San Antonio (M.J.Y.) for supporting the research activity. This work has been funded in part with funds from the NCI-NIH (Contract No. HHSN261200800001E). The contents of this publication do not necessarily reflect the views or policies of the DHHS, nor does mention of trade names, commercial products, or organizations imply endorsement by the US Government.


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Daniela A. Geraldo
    • 1
  • Esteban F. Duran-Lara
    • 1
  • Daniel Aguayo
    • 2
  • Raul E. Cachau
    • 3
  • Jaime Tapia
    • 1
  • Rodrigo Esparza
    • 4
  • Miguel J. Yacaman
    • 4
  • Fernando Danilo Gonzalez-Nilo
    • 2
  • Leonardo S. Santos
    • 1
    Email author
  1. 1.Laboratory of Asymmetric Synthesis, Chemistry Institute of Natural ResourcesUniversidad de TalcaTalcaChile
  2. 2.Center for Bioinformatics and Molecular SimulationsUniversidad de TalcaTalcaChile
  3. 3.Science Applications International Corporation (SAIC)-Frederick, Inc.National Cancer InstituteFrederickUSA
  4. 4.Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioUSA

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