Dispersive liquid-liquid microextraction of pesticides and metabolites from soils using 1,3-dipentylimidazolium hexafluorophosphate ionic liquid as an alternative extraction solvent.
In this work, the use of the ionic liquid (IL) 1,3-dipentylimidazolium hexafluorophosphate ([PPIm][PF₆]) as an alternative extractant for IL dispersive liquid-liquid microextraction (IL-DLLME) of a group of pesticides and metabolites (2-aminobenzimidazole, carbendazim/benomyl, thiabendazole, fuberidazole, carbaryl, 1-naphthol, and triazophos) from soils is described. After performing an initial ultrasound-assisted extraction (USE), the IL-DLLME procedure was applied for the extraction of these organic analytes from soil extracts. Separation and quantification was achieved by high-performance liquid chromatography (HPLC) with fluorescence detection (FD). Calibration, precision, and accuracy of the described USE-IL-DLLME-HPLC-FD method using [PPIm][PF₆] as an alternative extractant was evaluated with two soils of different physicochemical properties. Accuracy percentages were in the range 93-118% with RSD values below 20%. A comparison of the performance of [PPIm][PF₆] versus that of the so-common 1-hexyl-3-methylimidazolium hexafluorophosphate ([HMIm][PF₆]) was accomplished. Results indicate a comparable extraction efficiency with both ILs, being slightly higher with [HMIm][PF₆] for the metabolite 2-aminobenzimidazole, and slightly higher with [PPIm][PF₆] for triazophos. In all cases, LODs were in the low ng/g range (0.02-14.2 ng/g for [HMIm][PF₆] and 0.02-60.5 ng/g for [PPIm][PF₆]). As a result, the current work constitutes a starting point for the use of the IL [PPIm][PF₆] for further analytical approaches.
Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Química, Universidad de La Laguna-ULL, La Laguna-Tenerife, España.
María
M
Asensio-Ramos
Javier
J
Hernández-Borges
Lidia M
LM
Ravelo-Pérez
María M
MM
Afonso
J Antonio
JA
Palenzuela
Miguel Ángel
MÁ
Rodríguez-Delgado
D001562:Benzimidazoles / Q000032:analysis / Q000302:isolation & purification; D002219:Carbamates / Q000032:analysis / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D007093:Imidazoles / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry*; D059627:Liquid Phase Microextraction / Q000379:methods*; D009284:Naphthols / Q000032:analysis / Q000302:isolation & purification; D063086:Organothiophosphates / Q000032:analysis / Q000302:isolation & purification; D010573:Pesticide Residues / Q000032:analysis / Q000302:isolation & purification*; D015203:Reproducibility of Results; D012989:Soil Pollutants / Q000032:analysis / Q000302:isolation & purification*; D013050:Spectrometry, Fluorescence; D014230:Triazoles / Q000032:analysis / Q000302:isolation & purification
D001562:Benzimidazoles; D002219:Carbamates; D007093:Imidazoles; D052578:Ionic Liquids; D009284:Naphthols; D063086:Organothiophosphates; D010573:Pesticide Residues; D012989:Soil Pollutants; D014230:Triazoles; C029350:1-naphthol; C012584:triazophos