| In this work, carbonized cellulose nanoparticles have been prepared easily by heating filter paper in a mixture of
sulfuric acid and water. The nanoparticles were utilized as the dispersive solid phase extraction sorbent for the
extraction of diniconazole, clodinafob-propargyl, oxadiazon, chlorpyrifos, fenpropathrin, and fenoxaprop-p-ethyl
residues from orange, grape, pomegranate, and peach juices and fresh cucumber and onion juices. Initially, the
analytes in the aqueous sample were adsorbed onto the carbonized cellulose nanoparticles by vortex mixing.
Then the sorbent particles were isolated from the solution by centrifuging. Acetonitrile was used for elution of
the adsorbed analytes. Then, the obtained eluate was mixed with 1,2–dibromoethane and rapidly injected into an
aqueous solution. A turbid solution was obtained. It was centrifuged and an aliquot of the sedimented extractant
was injected into gas chromatography–flame ionization detector. The large surface area and hydrophilic nature
of the prepared sorbent provided its high extraction efficiency for the selected analytes and easy dispersibility
into the aqueous solutions. Performance characteristics of the proposed method were determined under the best
extraction conditions. The enrichment factor for all of the studied pesticides was more than 257. Limits of
detection and quantification were obtained in the ranges of 0.31–0.53 and 1.0–1.5 µg L–1
, respectively. The
relative standard deviations were in the ranges of 3–5 and 5–7% for intra– and inter–day precisions, respectively,
for six replicated determinations at a concentration of 50 µg L− 1 of each analyte. The presented method was used
for determination of the selected pesticides in various vegetable and fruit juices and oxadiazon was found in
onion juice at µg L–1 level. |