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2008 vol. 2
Breaking Down? Improve BDE-209 Response
Using a New Rtx®-1614 Column for PBDE Analysis
By Jason Thomas, Environmental Innovations Chemist, and Jack Cochran, Director of New Business and Technology
Polybrominated diphenyl ethers (PBDEs) are ubiquitous in humans and in the environment. Rapid and accurate PBDE methods
are increasingly in demand as adverse effects have been associated with PBDE exposure. EPA Draft Method 1614 presents a considerable
challenge to the analytical column due to the large number of PBDE compounds and stringent activity guidelines. One target com-
pound, decabromodiphenyl ether (BDE-209), is of particular concern as it is frequently encountered and is the primary component in
the only remaining commercial PBDE mixture. Column inertness is critical for BDE-209 analysis, as the breakdown mechanism is
predominately column-related.
EPA Draft Method 1614 stipulates a 5% phenyl methyl column in a 30m x
0.25mm x 0.10µm format with a shorter 15m column option. Here we compare
the performance of a method-specified column (DB-5HT) to the new Rtx®-1614
column, a 5% phenyl methyl column with a unique deactivation for maximum
inertness to BDE-209. Although this method requires analysis on a high-reso-
lution mass spectrometer, the columns were evaluated first on an Agilent 6890
GC with µ-ECD to assess inertness and general chromatographic performance.
Columns were then analyzed on an Agilent 7890/5975 GC/MS to verify separa-
tion requirements under vacuum outlet conditions.
The Rtx®-1614 column meets the method requirements for the resolution of critical pairs, tailing factors, and retention. The data in
Figure 1 demonstrate the separation of a large list of PBDEs on the Rtx®-1614 column; note the baseline resolution of congeners 49
and 71, which are required to have a 40% valley height of the smallest peak. The Rtx®-1614 column also performed exceptionally
well for inertness to BDE-209 (Table 1). Compared to the performance of the DB-5HT, shown in Figure 2, the Rtx®-1614 column
• Higher sensitivity and inertness for BDE-209 than the method-specified column, for more accurate, reproducible results.
• Meets all method requirements for resolution, tailing factors, and retention.
• Optimized short column conditions give improved BDE-209 response 3 times faster.
Figure 1
Separate PBDEs accurately and reliably on an Rtx®-1614 column.
Greater response
and higher inertness
for BDE-209!
Baseline resolution of
BDE-49 and BDE-71
1. BDE-10
2. BDE-7
3. BDE-8
4. BDE-11
5. BDE-12
6. BDE-13
7. BDE-15
8. BDE-30
9. BDE-32
10. BDE-17
11. BDE-25
12. BDE-28
13. BDE-33
14. BDE-35
15. BDE-37
16. BDE-75
17. BDE-49
18. BDE-71
19. BDE-47
20. BDE-66
21. BDE-77
22. BDE-100
23. BDE-119
24. BDE-99
25. BDE-116
26. BDE-118
27. BDE-85
28. BDE-155
29. BDE-126
30. BDE-154
31. BDE-153
32. BDE-138
33. BDE-166
34. BDE-183
35. BDE-181
36. BDE-190
37. BDE-208
38. BDE-207
39. BDE-206
40. BDE-209
Column:
Rtx
®
-1614, 30m, 0.25mm ID, 0.10µm (cat.# 10295)
Sample:
100-300ppb PBDE PAR Solution (cat.# EO-5113, Cambridge
Isotope Laboratories Inc.), 500ppb decabromodiphenyl
ether (cat.# BDE-209, Wellington Laboratories)
Inj.:
1µL splitless (hold 1 min.), 4mm cyclo double gooseneck
liner (cat.# 20896)
Inj. temp.:
300°C
Carrier gas:
helium, constant flow
Linear velocity: 20cm/sec. @ 100°C
Oven temp.:
100°C (hold 3 min.) to 320°C @ 5°C/min. (hold 15 min.)
Detector temp.: µ-ECD @ 340°C
GC_EV01019
Column
BDE-209 Average RRF*
Rtx
®
-1614 (15m)
0.681
Rtx
®
-1614 (30m)
0.636
DB-5HT (30m)
0.502
*Relative response factors based on internal standard
hexabromobiphenyl (n=5). Analyses run under optimized conditions.
Table I
Maximize BDE-209 response with an
Rtx®-1614 column, in 15 or 30m lengths!
Environmental