Analytical Methods Used for Assessment of Extractables
| Analytical Method | Target Compounds or Property | Water Extract | Ethanol Extract |
|---|---|---|---|
| Total organic carbon (TOC) | Total organic carbon content | ✓ | |
| pH | Change of acidity/alkalinity | ✓ | |
| Conductivity | Ability of conducting electric current | ✓ | |
| Ion chromatography (IC) | Acetate and formate | ✓ | |
| Non-volatile residue (NVR) | Total mass of extractables after evaporation of the test solvent | ✓ | ✓ |
| Fourier transform infrared spectroscopy (FTIR) | Qualitative analysis of unknowns, including oligomers of polymers | ✓ | ✓ |
| Ultraviolet spectroscopy (UV) | Compounds with chromophores | ✓ | ✓ |
| Gas chromatography/mass spectrometry Direct injection GC/MS | Semi-volatile organic compounds | ✓ | ✓ |
| Headspace GC/MS | Volatile organic compounds | ✓ | ✓ |
| Derivatization GC/MS | Organic acids, especially long chain fatty acids | ✓ | ✓ |
| High performance liquid chromatography/ultraviolet/ mass spectrometry (HPLC/UV/MS) | Additives from polymers | ✓ | ✓ |
| Inductively coupled plasma mass spectrometry (ICP/MS) | Metal elements | ✓ | ✓ |