Elsevier

Tetrahedron Letters

Volume 56, Issue 23, 3 June 2015, Pages 3653-3657
Tetrahedron Letters

Binding studies of cucurbit[7]uril with gold nanoparticles bearing different surface functionalities

Dedicated to the memory of Harry Wassserman, a true Renaissance man
https://doi.org/10.1016/j.tetlet.2015.04.125Get rights and content

Abstract

Host–guest interactions between a synthetic receptor, cucurbit[7]uril (CB[7]), and gold nanoparticles (AuNPs) have been quantified using isothermal titration calorimetry. AuNPs were functionalized with ligands containing tertiary or quaternary benzylamine derivatives, with electron donating or withdrawing groups at the para position of the benzene ring. Analysis of binding interactions reveals that functional groups at the para position have no significant effect on binding constant. However, headgroups bearing a permanent positive charge increased the binding of AuNPs to CB[7] ten-fold compared to monomethyl counterparts.

Section snippets

Result and discussion

We have designed a series of nanoparticles with benzylammonium terminal group possessing different functionalities at the para position of the benzene ring, which is the least sterically hindered position for binding process based on the reported crystal structures of cucurbiturils.50, 51 Seven quaternary amine (DMBA) and five tertiary amine (MMBA) derivatives (Fig. 1) were synthesized to represent a wide range of functionalities that bring at least one of the following attributes to the

Conclusion

We have used isothermal titration calorimetry to monitor the binding interactions of CB[7] with twelve different AuNPs. Binding studies revealed that NP1–NP7 possessing DMBA head groups showed a higher binding affinity toward CB[7] compared to NP8–NP12 having MMBA head groups. Insertion of the tBu group at the para position of the benzene ring led to a lower binding due to the steric effect. Although not very strong difference in Ka constants was observed between electron donating and

Acknowledgements

This work was supported by the NIH (NIH R01 EB014277). T.M. is grateful to the Japan Society for the Promotion of Sciences (JSPS) for a Postdoctoral Fellowship for Research Abroad and for the Strategic Young Researcher Overseas Visits Program for Accelerating Brain Circulation.

References and notes (63)

  • D. Mink et al.

    Tetrahedron Lett.

    (1998)
  • H.M. Chawla et al.

    Tetrahedron Lett.

    (2012)
  • J. Rubio et al.

    Tetrahedron Lett.

    (2010)
  • P. Ghosh et al.

    Adv. Drug Deliv. Rev.

    (2008)
  • S.T. Kim et al.

    Acc. Chem. Res.

    (2013)
  • H. Kuang et al.

    Biosens. Bioelectron.

    (2011)
  • J.M. Lehn

    Science

    (1985)
  • J.M. Lehn

    Proc. Natl. Acad. Sci. U.S.A.

    (2002)
  • M.C.T. Fyfe et al.

    Accounts Chem. Res.

    (1997)
  • J. Bradley et al.

    Angew. Chem., Int. Ed.

    (2001)
  • S.Y. Dong et al.

    Accounts Chem. Res.

    (2014)
  • B.J. Jordan et al.

    Chem. Commun.

    (2008)
  • K. Liu et al.

    Adv. Mater.

    (2013)
  • Y. Gu et al.

    Angew. Chem., Int. Ed.

    (2014)
  • R. Gramage-Doria et al.

    Angew. Chem., Int. Ed.

    (2014)
  • X.M. Yao et al.

    Macromol. Rapid Commun.

    (2014)
  • P.S. Ghosh et al.

    ACS Nano

    (2008)
  • L. Fabbrizzi et al.

    Chem. Soc. Rev.

    (1995)
  • S.G. Elci et al.

    Chem. Sci.

    (2013)
  • F. Biedermann et al.

    Chem. Eur. J.

    (2010)
  • C.N. Carroll et al.

    Chem. Soc. Rev.

    (2010)
  • H. Li et al.

    Proc. Natl. Acad. Sci. U.S.A.

    (2004)
  • C. Subramani et al.

    Chem. Commun.

    (2010)
  • C.A. Hunter et al.

    J. Am. Chem. Soc.

    (1990)
  • K. Kim

    Chem. Soc. Rev.

    (2002)
  • C. Marquez et al.

    J. Am. Chem. Soc.

    (2004)
  • D. Zhao et al.

    Chem. Commun.

    (2003)
  • P. Pengo et al.

    J. Mater. Chem.

    (2003)
  • I. Hussain et al.

    J. Am. Chem. Soc.

    (2005)
  • F.G. de Rivera et al.

    J. Organomet. Chem.

    (2012)
  • C.K. Kim et al.

    J. Am. Chem. Soc.

    (2009)
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