ABSTRAK
Metode penetapan multi-residu pestisida telah dikembangkan melalui modifikasi metode QuEChERS pada metode EN 15662:2008 untuk mendapatkan prosedur ekstraksi dan clean-up yang sesuai dengan contoh yang mengandung kadar lemak tinggi yaitu kakao. LC-ESI-MS/MS digunakan untuk kuantisasi dan konfirmasi terhadap 18 pestisida pada biji kakao. Contoh biji kakao diekstraksi menggunakan asetonitril (1% asam asetat) diikuti dengan penambahan MgSO4, NaCl, Na3C6H5O7.2H2O dan Na2C6H6O7.1,5H2O. Kemudian dilakukan prosedur clean-up terhadap ekstrak dengan menambahkan PSA, C18, dan MgSO4. Mode Multiple Reaction Monitoring (MRM) digunakan dengan memilih dua transisi ion untuk setiap pestisida. Efek matriks dikompensasi dengan menggunakan kurva standar matrix-matched. Metode ini divalidasi berdasarkan acuan SANCO/1495/2011. Linearitas semua senyawa pestisida memiliki nilai R = 0,99. Presisi (Repeatabilitas) dari 17 pestisida berada pada rentang 2,48% sampai 18,61%. Recovery dari 15 pestisida diperoleh pada rentang 70,32%±10,72% sampai 128,26%±5,17%. Nilai Linearitas, Presisi dan Recovery yang diperoleh telah memenuhi persyaratan yang ditetapkan dalam dokumen SANCO/12571/2013. Kata Kunci : Kakao, QuEChERS, EN 15662/2008, LC-ESI-MS/MS, Presisi, Recovery, Efek Matriks.
ABSTRACT A
method for the determination of multi-residue of pesticide was developed by modification of QuEChERS method in EN 15662:2008 Standard Method to obtain extraction and clean-up procedure in high fatty sample, namely cocoa bean. LC-ESI-MS/MS was used for the quantification and confirmation of 18 pesticides in cocoa bean. Cocoa samples were extracted using acetonitrile (1% acetic acid) followed by partitioning with MgSO4, NaCl, Na3C6H5O7.2H2O and Na2C6H6O7.1,5H2O. The extract was clean-up using PSA, C18, and MgSO4. Multiple Reaction Monitoring (MRM) mode, choosing two transition ions per analyte was applied. Matrix effect was compensated using the matrix matched calibration curves. This method has validated according to the requirements of SANCO/12495/2011. Acceptable linearity all of pesticide in R = 0,99. Precision (repeatability) of 17 pesticide were ranged from 2,48% to 18,61%. Recoveries of 15 pesticides were ranged from 70,32%±10,72% to 128,26%±5,17%. Linearity, repeatability and recoveries obtained were in accordance with the performance criteria required by document SANCO/12571/2013. Keywords : Cocoa, QuEChERS, EN 15662/2008, LC-ESI-MS/MS, Precision, Recovery, Matrix Effect.