African Journal of
Pure and Applied Chemistry

  • Abbreviation: Afr. J. Pure Appl. Chem.
  • Language: English
  • ISSN: 1996-0840
  • DOI: 10.5897/AJPAC
  • Start Year: 2007
  • Published Articles: 357

Full Length Research Paper

NMR and fluororescence enhancement effect studies of ternary inclusion complexes among naphthalenediamines-triethylene tetramine modified -cyclodextrin-lanthanide metal ions

Huiming Jiang1,2*, Shufen Zhang1, YingZhi Cui2, Yu Xie2 and Qi Shi2
1State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012, Liaoning, China. 2College of Life Science, Dalian Nationalities University, Dalian, 116600, Liaoning China.
Email: [email protected]

  •  Received: 12 August 2009
  •  Accepted: 18 April 2011
  •  Published: 30 June 2011

Abstract

The 6-OH group of b-cyclodextrin (b-CD) was modified by triethylene tetramine. The modified host molecule successfully complexes 1,5-naphthalenediamine and 1,8-naphthalenediamine, respectively, in the presence of lanthanide metal ions (Y3+, Yb3+, Nd3+, Sm3+). As a result, eight ternary inclusion complexes (host-guest-metal) were formed, which were characterized via 1H nuclear magnetic resonance (NMR) technique. The chemical shift variations of host and guest molecules were studied. The stoichiometric proportion of host and guest molecules is 2:1 for all the eight complexes. Signal degeneration still exists for the guest molecules after the inclusion, which verifies the symmetrical conformation of the guest molecules inside the cavities of the two host molecules. After the inclusion process, we found that the fluorescent strength of guest molecules was increased in a remarkable degree in this series, meanwhile, the fluorescent strength of 1,5-naphthalenediamine was higher than that of 1,8-naphthalenediamine by 3 to 4 times, which verifies that 1,8-naphthalenediamine coordinates with lanthanide metal ions, however, similar coordination does not occur in the case of 1,5-naphthalenediamine.
 
Key words: b-Cyclodextrin (b-CD), modification, naphthalenediamine, lanthanide metal, nuclear magnetic resonance (NMR), fluorescence, complexation.

Abbreviation

CD, Cyclodextrin; NMR, nuclear magnetic resonance; TSPP, tetrasodium pyrophosphate; DMSO, dimethyl sulfoxide.