hops extract was spiked with aflatoxins at corresponding concentrations of 6 ppb each (for Aflatoxin B2 and G2) and 24 ppb each (for Afltoxin B1 and G1) in hops
Supel Tox AflaZea SPE, 6 mL (55314-U)
0.5 g of finely ground hops is mixed with 10 mL of 84:16 acetonitrile:water for 30 minutes, centrifuged
2 mL of hops sample extract
apply strong vacuum and collect the sample into plastic tube
dilute 0.2 mL of the extract with 0.8 mL distilled water and mix well
Ascentis Express Phenyl-Hexyl, 5 cm x 2.1 mm I.D., 2.7 μm particles (53334-U)
[A] 5 mM ammonium formate with 1% formic acid in water; [B] 5 mM ammonium formate with 1% formic acid in methanol
30% B to 60% B in 3 min; to 100% B in 2 in; held at 100% B for 2 min; to 30% B in 0.1 min; held at 30% B for 1.4 min
0.4 mL/min
5511 psi (380 bar)
40 °C
MS, ESI(+), MRM 331.3/189.0, 329.1/243.0, 315.9/259.0, 313.1/241.0
10 μL
The complex composition of hops makes it difficult to apply sample cleanup methods commonly used for other commodities. In this application, interference removal on Supel Tox AflaZea SPE was used for sample cleanup providing quick and effective sample preparation prior to separation on an Ascentis Express Phenyl-Hexyl column and mass spectrometric detection. It is recommended to use silanized glass vials for this analysis.
Use silanized vials for analysis.
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