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Determination of Polycyclic Aromatic Hydrocarbons in Cooked Beef by Low-Temperature Molecular Luminescence Spectrometry. The cooked beef sample was ground in a meat grinder. A 150-g sample was transferred to a round-bottom flask, where it was boiled in methanolic KOH for four hours.
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Determination of Polycyclic Aromatic Hydrocarbons in Cooked Beef by Low-Temperature Molecular Luminescence Spectrometry
The cooked beef sample was ground in a meat grinder. A 150-g sample was transferred to a round-bottom flask, where it was boiled in methanolic KOH for four hours. The saponified sample was then extracted twice with cyclohexane. The cyclohexane layer was extracted twice with DMF, and, finally, the DMF layer was extracted twice with n-hexane. The n-hexane layer was evaporated to 10 mL on a rotary evaporator, quantitatively transferred to a 25-mL volumetric flask, and diluted to the mark with additional n-hexane. The entire extraction procedure required approximately eight hours for completion. No further sample preparation steps were taken.
Combined Internal Standard – Standard AdditionAnalysis of urine by W-coil ETV-ICP • 1 mL urine mixed with 1 mL water • 2 µL of 1000 ppm Bi added (int. std.) • Cd added as standard additions • No acid • No digestion • No Hydrogen in W-Coil gas • 54 heating cycles per coil