Determination of poorly fluorescent carbamate pesticides in water, Bendiocarb and Promecarb, using cyclodextrin nanocavities and related media.

NATALIA L. PACIONI; ALICIA VIVIANA VEGLIA

ANALYTICA CHIMICA ACTA

Elsevier

Lugar: Shannon (Ireland); Año: 2007 vol. 583 p. 63 - 63

0003-2670

he effect of native cyclodextrins (a, b, or gCD with six, seven and eight glucose units, respectively), hydroxypropyl--cyclodextrin (HPCD), chitosan (CHT) and glucose in water solution or water with n-propylamine (PA) as co-solvent upon the UV?vis and fluorescence properties of poorly fluorescent N-methyl carbamates pesticides (C) as bendiocarb (2,2-dimethyl-1,3-benzodioxol-4-ol methylcarbamate, BC) and promecarb (3-methyl-5-(1-methylethyl)phenol methylcarbame, PC) was examined. Fluorescent enhancement was found for both substrates with all CDs in water or PA-water except from PC with CD. The addition of CHT increases the fluorescence of BC but decreases the fluorescence of PC, and glucose addition gives in both cases no spectral changes. Host-guest interaction was clearly determined by fluorescence enhancement with CD and HPCD with a 1:1 stoichiometry for the complexes (C:CD). The values obtained for the association constants (KA, M−1) were (6 ± 2) × 102 and (2.3 ± 0.3) × 102 f