A mixture of eight pesticides was prepared utilizing ACN as a solvent. (See Analysis Note for more information. )
Chromolith® Performance 50 x 2 mm (1.52007.0001)
[A] ACN + 0.1% FA; [B] water + 0.1% FA;
20% A; to 80% A in 6 min; to 70% A for 1 min; to 20% A in 1 min; (Original: 0′ 20% A, 6′ 80% A, 7′ 80% A, 8′ 20% A)
0.4 mL/min
420 psi (29 bar)
25 °C
Bruker ESI-MS, m/z 190-370, BPC (1.4 μL)
1.0 μL
Metamitron 159 mg/L, Carbetamid 487 mg/L, Prometryn 60 mg/L, Carbofuran 548 mg/L, Isoproturon 159 mg/L, Metazachlor 796 mg/L, Metolachlor 395 mg/L, Chlorfenvinphos 300 mg/L spiked in porcine kidney
Concentrations of the analytes in the stock solution was as follows: Metamitron 159 mg/L, Carbetamid 487 mg/L, Prometryn 60 mg/L, Carbofuran 548 mg/L, Isoproturon 159 mg/L, Metazachlor 796 mg/L, Metolachlor 395 mg/L, Chlorfenvinphos 300 mg/L.
For the preparation of a porcine kidney sample 10 mL of ACN/water 20/80 (v/v) was added to approximately 1 g of kidney. After homogenization utilizing a GRINDOMIX GM 200 knife mill (Retsch, Haan, Germany) the sample was centrifuged at 4500 rpm for 20 min. The yellowish to reddish supernatant was decanted off and acetonitrile was removed during 120 min and 50 °C under nitrogen stream (1 bar) using a TurboVap II (Biotage, Uppsala, Sweden). In order to remove salts and tissue the residue was transferred to a LiChrolut RP-18e 500 mg cartridge (Merck KGaA, Darmstadt, Germany) conditioned with ACN and water prior to use.
After a typical SPE protocol the yellow band was eluted with 5 mL ACN. 2.5 mL of water was added to the eluate and after another concentration step (40 min, 50 °C, 1 bar nitrogen) the sample was filtered using a 0.45 μm syringe filter (Merck KGaA, Darmstadt, Germany) and transferred to HPLC vials. Spiking of the kidney extract was performed prior to the solid phase extraction process by adding 2 mL of stock solution.
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