Probing the interaction of caffeic acid with ZnO nanoparticles.
Luminescence
; 31(3): 654-9, 2016 May.
Article
in En
| MEDLINE
| ID: mdl-27037967
ABSTRACT
The binding of ZnO nanoparticles (NPs) and caffeic acid (CFA) was investigated using fluorescence quenching, UV/vis absorption spectrscopy, Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and dynamic light scattering (DLS) at different temperatures. The study results indicated fluorescence quenching between ZnO NPs and CFA rationalized in terms of a static quenching mechanism or the formation of non-fluorescent CFA-ZnO. From fluorescence quenching spectral analysis, the binding constant (K(a)), number of binding sites (n) and thermodynamic properties were determined. Values of the quenching (K(SV)) and binding (K(a)) constants decrease with increasing temperature and the number of binding sites n = 2. The thermodynamic parameters determined using Van't Hoff equation indicated that binding occurs spontaneously involving the hydrogen bond, and van der Waal's forces played a major role in the reaction of ZnO NPs with CFA. The FTIR, TEM and DLS measurements also indicated differences in the structure, morphology and size of CFA, ZnO NPs and their corresponding CFA-ZnO.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Zinc Oxide
/
Caffeic Acids
/
Nanoparticles
Language:
En
Journal:
Luminescence
Journal subject:
BIOFISICA
/
BIOQUIMICA
Year:
2016
Document type:
Article