Characterization of aqueous and solid inclusion complexes of diuron and isoproturon with beta-cyclodextrin.
The interaction of diuron and isoproturon herbicides with beta-cyclodextrin is conducive to the formation of inclusion compounds in aqueous solution as well as in the solid state. The physico-chemical study of these complexes was carried out by various analytical techniques such as ultraviolet (UV), Fourier transform infrared (FT-IR), Raman, X-ray diffraction, and 1H-NMR (nuclear magnetic resonance) spectroscopies. The existence of inclusion complexes in water solution between the beta-cyclodextrin and each of the herbicides was revealed by electronic absorption and 1H-NMR spectroscopies. A 1:1 stoichiometry was determined for both complexes in aqueous medium from UV absorption spectra by using the Benesi-Hildebrand method; the relative stability constants at room temperature were calculated at 2700 +/- 300 L mol(-1) and 750 +/- 50 L mol(-1) for isoproturon and diuron, respectively. In the solid state, inclusion processes with beta-cyclodextrin were characterized by means of infrared and Raman techniques and confirmed by X-ray diffraction spectra.
Dupuy
N
N
Laboratoire de Spectrochimie Infrarouge et Raman, UMR CNRS 8516, Centre d'Etudes et de Recherches Lasers et Applications, Bât. C5, Université des Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq, France.
Marquis
S
S
Vanhove
G
G
Bria
M
M
Kister
J
J
Vrielynck
L
L
D003505:Cyclodextrins / Q000032:analysis / Q000737:chemistry*; D004237:Diuron / Q000737:chemistry*; D006540:Herbicides / Q000737:chemistry*; D008782:Methylurea Compounds / Q000737:chemistry*; D010671:Phenylurea Compounds; D012996:Solutions; D013053:Spectrophotometry / Q000379:methods*; D013269:Stochastic Processes; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction / Q000379:methods; D047392:beta-Cyclodextrins
D003505:Cyclodextrins; D006540:Herbicides; D008782:Methylurea Compounds; D010671:Phenylurea Compounds; D012996:Solutions; D047392:beta-Cyclodextrins; D014867:Water; C028904:isoproturon; D004237:Diuron; C031215:betadex