Mohammad Reza Rezaei Kahkha - Department of Environmental Health Engineering, Faculty of Health, Zabol University of Medical Sciences, Zabol, Iran
Massoud Kaykhaii - Department of Chemistry, Faculty of Sciences, University of Sistan and Baluchestan, Zahedan, Iran
Mahdi Shafee-Afarani - Department of Material Engineering, University of Sistan and Baluchestan, Zahedan, Iran
Batool Rezaei Kahkha - Department of Occupational Health Engineering, Kerman University of Medical Sciences, Kerman, Iran

In this work, a microextraction technique based on pipette tip solid-phase extraction was used for preconcentration and determination of diazinon. Carbon nanotube functionalized by zinc sulfide and ethylene glycol was used as sorbent. Determination of diazinon was performed using high performance liquid chromatography and UV detection. Important parameters that influence the extraction efficiency (i.e. pH, amount of adsorbent, extraction time, salt addition, volumes of sample and eluting solvent and number of aspirating/dispensing cycles for both solvent and sample) were investigated and optimized. Results were showed that method was validated over the range of 0.50 - 100.0 µg L-1. Repeatability was satisfactory, bellow 3.78% for 5 replicate measurements of 20 µg L-1 of diazinon. The limit of detection of this method is 0.03 µg L-1 with an enrichment factor of 100 and short extraction time of 8.5 min, which confirmed suggested method is a reliable and accurate for extraction and preconcentration of diazinon.

Carbon nanotubes, Diazinon, Pipette Tip, Preconcentration, solid phase extraction