Caffeine from Coffee

Immobilized Liquid Extraction (ILE) Caps may be utilized to quantifiably extract flavor or other components of beverages. An example of this is the extraction of caffeine from brewed coffee. A 20mL coffee sample was placed in a 40mL VOA vial. 100µl of methylene chloride was added to the sample to enhance partitioning from the sample into the immobilized solvent (polymer). The sample vessel was sealed with a PDMS ILE Cap, inverted, and agitated for 30 minutes to allow sufficient partitiong. The analyte-laden ILE Cap was removed from the sample vessel and placed on a high-recovery vial containing 200µL acetone. This vial was inverted and agitated for 30 minutes to allow analytes to desorb into the acetone. The resulting extract was analyzed by an HP-5971 GC/MS in scan mode with a 30m x 0.25mm i.d. X 0.25µm VB-5 column. The chromatogram is shown below.