Alcohol
- Page ID
- 65200
Analysis of a Simulated Blood Sample for Ethanol
Objective
To determine the concentration of ethanol in a blood sample; to see if the person being tested was legally drunk.
Sample
A simulated blood plasma with added ethanol. Store the aqueous solution in a tightly closed vial in the refrigerator; the solution is stable for at least one month.
Preparation of Simulated Blood Plasma
Draw a small amount of yellow food coloring into a Pasteur pipette and squirt it out again. Rinse the pipette with deionized water and dilute the rinsings to about 10 mL. Add a few drops of this colored solution to the volumetric flask, in which the analyte sample is being prepared, to approximate the pale yellow color of blood plasma.
Reagents
Ethanol (analyte), n-propanol (internal standard)
Standard Reference Material
The standard reference material is simulated blood plasma with a concentration of 0.10% (w/v) ethanol. Store the aqueous solution in a tightly closed vial in the refrigerator; the solution is stable for at least one month.
Method
Gas chromatography; direct aqueous injection
Special Equipment
Capillary gas chromatograph with thick-film Carbowax column (e.g. 30 m x 0.25 mm x 0.5 µm) and flame ionization detector
Procedure
For instructor (detailed); For student (brief)