How should I go about diluting essential oil to 25 ppm with hexane?

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Arlette Jiménez Silva

Hi Jolene. How about this?

Step A: Weigh 0.25 g of the essential oil in a 10 mL- volumetric flask. Fill up with n-hexane and mix thoroughly.= 25000 ppm

Step B: 0.10 mL A (micropipette) in 10 mL volumetric flask. Fill up with n-hexane = 250 ppm.

Step C: 1.00 mL B in 10 mL volumetric flask: 25 ppm.

Best regards.

Ibrahim Sani

Deuterated hexane would be much suitable for the dilution instead of n-hexane to avoid molecular interference.

Solomon Habtemariam

One part per million (ppm) equates to 1 mg/L. You are far better of working with weight-based calculation like this for your essential oil instead of volume. So, weigh out a drop of your oil in a glass vial and dilute it to 25 mg per liter in hexane to make up 25 ppm.