Determination Of Organophosphorus Pesticide Residues In Several Local Vegetables Using Solid Phase Microextraction Coupled With Gas Chromatography

• Main Author: Sapahin, Haizarul Aida
• Format: Thesis
• Language: English
• Published: 2016
• Subjects: QD1-999 Chemistry
• Online Access: http://eprints.usm.my/31791/1/HAIZARUL_AIDA_BINTI_SAPAHIN_24%28NN%29.pdf; http://eprints.usm.my/31791/

Kaedah analisis yang mudah dan tepat iaitu pengekstrakan mikro fasa pepejal (SPME) bagi menentukan 11 residu pestisid jenis organofosforus (etoprofos, sulfotep, diazinon, tolklofos-metil, fenitrotion, klorpirifos, isofenfos, metidation, etion, triazofos, leptofos) dalam tiga jenis sayur – sayuran tempatan (kobis, kailan, sawi) telah dibangunkan menggunakan alat kromatografi gas dengan pengesan fotometri nyala (GC-FPD). Parameter penting yang mempengaruhi kecekapan pengekstrakan (jenis gentian, kaedah pengekstrakan, masa pengekstrakan, penambahan garam, masa dan suhu penyaherapan) telah dikaji secara sistematik. Perbandingan empat jenis gentian yang biasa digunakan secara komersial iaitu 50/30 μm divinilbenzena / Carboxen / polidimetilsiloksana (DVB / CAR / PDMS), 65 μm polydimetilsiloksana / divinilbenzena (PDMS / DVB), 100 μm polidimetilsiloksana (PDMS) dan 85 μm poliakrilat (PA) telah dilakukan. Gentian jenis PA menunjukkan prestasi yang terbaik dan telah digunakan untuk mendapatkan keadaan yang optimum dan digunakan untuk kaedah tentusah. A simple analytical method based on solid-phase microextraction (SPME) followed by gas chromatography-flame photometric detection (GC-FPD) for the simultaneous determination of eleven organophosphorus pesticide residues (ethoprophos, sulphotep, diazinon, tolclofos-methyl, fenitrothion, chlorpyrifos, isofenphos, methidathion, ethion, triazophos, leptophos) in three types vegetables samples (cabbage, kale and mustard) was developed. Important parameters that influence the extraction efficiency (i.e., fibre type, extraction modes, extraction time, salt addition, desorption time and temperature) were systematically investigated. Four types of commercially available fibres namely 50/30 μm divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS), 65 μm polydimethylsiloxane/divinylbenzene (PDMS/DVB), 100 μm polydimethylsiloxane (PDMS), and 85 μm polyacrylate (PA) were evaluated. PA fibre exhibited the best performance and was used for the rest of the studies.