Automated Low Background Solid Phase Extraction of Perfluorinated Compounds in Water

Oral Presentation

Prepared by G. Jeter
Fluid Management Systems, 580 Pleasant Street, Watertown, MA, 02472, United States


Contact Information: [email protected]; 617-393-2396


ABSTRACT

Perfluoralkylated compounds contain a perfluorinated or polyfluorinated carbon chain moiety such as F(CF2)n- or F(CF2)n-(C2H4)n. In recent years there has been increasing concern over the levels of these chemicals, (e.g., PFOS (perfluorosulfonate), and PFOA (perfluoro-octanoicacid)) in the global environment because of their fate and possible adverse effects. PFOS are now subject to varying but increasing levels of control in a number of countries. This study demonstrates the first automated solid phase extraction system made specifically for PFC extraction and concentration. Primarily effective at reducing background contamination, extraction and concentration of aqueous samples takes less than two hours.

500 mL water samples were spiked with 25 uL of a 1 ug/mL PFC standard solution. Samples were then loaded onto the PFC SPE system and passed across an HLB Plus 225 mg cartridge under -12 psi vacuum. After loading, the bottle was rinsed with 25 mL of water and loaded onto the cartridge under negative pressure. The cartridges were dried using nitrogen until no residual water was present, and then subsequently eluted with methanol. The extracts were concentrated to 500 uL, after which internal standard was added. The samples were diluted to a final volume of 1 mL for LC/MS analysis.

Extracts analyzed with LC/MS/MS confirms that background from this system ranges from undetectable (PFUdA) to 0.214 (PFOA) ng/L of sample. Preliminary data shows recoveries of PFCs > 90%.