Sample preparation
Sample preparation - contextSample preparation - motivationPurpose of sample preparationOverview of preparation methods
Liquid liquid extraction (LLE) Solid phase extraction (SPE) Solid phase microextraction (SPME) Purge and trap (PT) (Accelerated) Solvent extraction ((A)SE) 
Supercritical fluid extraction (SFE) Filter Techniques (FT)
Box 10 FiltrationBox 11 SorbentsBox 12 Preconcentration
Selftest 1) Polar organic solvent Answer 2) Ideal extraction procedures Answer 3) SPME Answer 4) Extraction efficiency Answer 5) Sorption capacity Answer 6) Use as little of an extraction medium as possible Answer 7) Should soil samples be grinded? Answer 8) Solvent volume Answer 9) Extracting an air sample AnswerProblems
End of chapter8) Solvent volume
Question:
Assume that 100 ml of a solvent were needed to extract a sample. Does it make sense to subsequently reduce the solvent volume (by evaporation) to 10 ml in order to increase the concentration of the analyte? Are there solvents that are better suited for this than others?
Answer:
Reducing the solvent volume does make sense as long as (almost) no analyte gets lost during this procedure. This will depend on the partition coefficient of the analyte between the solvent and air and the saturated vapor pressure of the solvent. The lower the first (i.e., the lower the partitioning into air), the better (i.e., the less analyte is lost).
See also Problem 3
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