coktail of anesthetics- extraction method

[filadianet]

hello everybody,
Can someone help me to give an information about how can I do a extraction when I have a coktail of anesthetics?
The matrix is whole blood. This coktail contents: propofol, phentanil, diazepam, and other different substances.
It will help me if someone can tell what sovent I can use, pH? Any information is good. After extraction I use a GC/MS, for identification
thanks a lot, diana

[Jetjamnong]

Dear diana,
I use mixed mode SPE (Bond-Elute) to extract these compounds by using 0.5 mL of blood and elute with mixed solvent, Dichloromethane/Acetone follow by Ethyl acetate/NH4OH and Dichloromethan/IPA/NH4OH. After evaporation to dryness, reconstitute with 20% ACN 0.1 mL and LC/QTOF analysis.
This procedure can be use with GC/MS by changing resolving solution to Ethyl acetate instead of 20% ACN.