Organophosphorus pesticides
CONDITIONS
sample/matrix
50 ppb each in 1.5 mL saturated salt water, pH 7.2
SPME fiber
polydimethylsiloxane, 100 μm (57300-U)
extraction
20 min immersion with rapid stirring
column
5% phenyl polysiloxane, 30 m × 0.25 mm I.D., 0.25 μm (Supelco equivalent, SLB-5ms, 28471-U)
oven
60 °C (1 min) to 300 °C at 12 °C/min, hold 5 min
inj. temp.
splitless (0.75 mm I.D. liner), 270 °C
detector
MS (m/z = 45-400, 0.6sec/scan)
carrier gas
helium, 30 cm/sec