Page 48 - Application Notebook - PFAS Analysis

No. SSI-LCMS-121

MRL in MRL in
ISTD Collision
ID# Compound Type m/z RT vial sample R2
Group# Energy, V
(ng/mL) (ng/L)
30 M8PFOS Surrogate 3 507.00>80.00 15.75 12 ---- ---- ----
31 M9PFNA Surrogate 1 472.00>427.00 15.73 11 ---- ---- ----
32 PFOS Target 2 498.90>80.10 15.23 45 0.05 0.2 0.9952
33 M4PFOS ISTD 2 503.00>80.00 15.76 45 ---- ---- ----
34 9Cl-PF3ONS Target 1 530.90>351.00 16.5 54 0.025 0.1 0.9954
35 8-2 FTS Target 2 527.00>507.00 16.97 27 1 4 0.997
36 M2-8-2 FTS Surrogate 2 529.00>509.00 16.98 26 ---- ---- ----
37 PFDA Target 1 512.90>468.90 17.04 26 0.025 0.1 0.9952
38 MPFHxA Surrogate 1 318.00>273.00 10.48 12 ---- ---- ----
39 PFUnA Target 1 562.90>519.00 18.14 11 0.025 0.1 0.9948
40 M7PFUnA Surrogate 3 570.00>525.00 18.11 12 ---- ---- ----
41 11Cl-PF3OUdS Target 1 630.70>451.00 18.63 12 0.025 0.1 0.9953
42 PFDoA Target 1 612.90>568.90 19.06 30 0.025 0.1 0.9951
43 M2PFDoA Surrogate 3 615.00>570.00 19.06 10 ---- ---- ----
44 MPFDA Surrogate 1 519.00>474.10 17.04 12 ---- ---- ----

Calibration
Standards available from Wellington Laboratories During this study, an Initial Calibration curve was ran
were used for these studies (EPA method analyte 5 consecutive days. Figure 2 shows an aggregate
stock 2 mL volume in methanol at 1 ug/L, Internal calibration curve for PFMPA and PFPeA and Figure 3
standard in methanol Wellington Catalog No. 533-IS shows an aggregate calibration curve for PFDA and
and Isotope Dilution Analogue PDS in Methanol example MRL 0.1 ng/L chromatogram. The
Wellington Catalog No. 533-ES). These standards chromatogram shown in Figure 4 is from a level 7, 6
were then diluted to working standards as outlined ng/L calibrator. Figure 5 shows a clean instrument
in Section 7.17.5 of EPA Method 533 using 20% blank (80:20 MeOH:H2O), indicating that the system
water in methanol as diluent to match the extract is free from PFAS contamination as no PFAS was
solvent composition. The working standards were detected.
used to create a calibration curve ranging from 1
ng/L to 1000 ng/L for NFDHA, and from 0.1 ng/L to
100 ng/L for all other analytes.

Figure 2: Aggregate calibration curves for PFMPA, and PFPeA.