ADV06-15_1-412

• 10 •

2008 vol. 2

Environmental

Polycyclic aromatic hydrocarbons (PAHs) are envi-

ronmental contaminants resulting primarily from

the incomplete combustion of organic materials.

PAHs are an increasing human health concern, as

this group of chemicals includes several known or

suspected carcinogens. Exposure usually occurs by

eating charbroiled foods, inhaling fumes from

automobile or industrial emissions, or from other

sources such as burning coal, wood, and tobacco.

PAHs are also present in some medicines, plastics,

and pesticides. National and international regula-

tory agencies provide target analyte lists and,

although these lists are not identical, a number of

compounds are common across the recommended

lists. Here we analyze target compounds from the

United States Environmental Protection Agency

(EPA), European Union (EU), and Portugal lists by

UHPLC and HPLC. Procedures shown use opti-

mized stationary phases and provide analysis times

of 3.5 to 6 minutes, allowing labs to achieve signif-

icantly faster sample throughput.

Two Phases Optimized for PAHs

Although most HPLC methods recommend a C18

column, the Pinnacle™ II PAH and Pinnacle™ DB

PAH stationary phases both have been optimized

specifically for polycyclic aromatic hydrocarbons

and offer greater selectivity for these compounds.

Pinnacle™ II PAH columns are available in stan-

dard formats, while the Pinnacle™ DB PAH columns are offered on 1.9µm silica. To demonstrate the fast analysis times and optimal

selectivity of these phases, US, EU, and Portugal lists were analyzed on 1.9µm Pinnacle™ DB PAH columns using ultra-high pres-

sure liquid chromatography (UHPLC). Portugal PAHs were also analyzed isocratically on a Pinnacle™ II PAH (50mm x 3.2mm,

4µm) column. Conventional HPLC was used for the Portugal list because, since only five analytes are included on the target list, fast

analysis times and high sample throughput can be achieved without the high backpressures associated with UHPLC.

Fully Resolve PAHs in 3.5 to 6 Minutes

The 1.9µm Pinnacle™ DB PAH column resolved all 18 US EPA 610 analytes in less than 3.5 minutes (Figure1). The column was held

at a constant temperature of 30°C to improve overall peak shape. The priority PAHs included in EU recommendation 256/2005 were

also analyzed on the 1.9µm Pinnacle™ DB PAH column and were separated in less than 6 minutes (Figure 2). Using the 1.9µm

Pinnacle™DB PAH column pairs the stationary phase’s high selectivity for PAHs with the increased efficiency and fast analysis times

of UHPLC. The Portugal PAH list was analyzed by UHPLC (data not shown), but was also analyzed by conventional HPLC using a

4µm Pinnacle™ II PAH column. All target analytes were resolved in less than 4 minutes (Figure 3).

For the analysis of polycyclic aromatic hydrocarbons, two stationary phases provide optimum results. The Pinnacle™ II PAH phase

is available in standard column dimensions while the Pinnacle™ DB PAH phase is available in 1.9µm particle size dimensions. Both

alkyl phases have been optimized specifically for PAHs and offer exceptionally fast analysis times, providing a significant opportu-

nity to labs interested in increasing sample throughput.

Acknowledgement

Thanks to JASCO for supplying the JASCO X-LC system used for this work.

Increase Polycyclic Aromatic Hydrocarbon

Sample Throughput

With UHPLC and HPLC Column Options

By Michelle Long, Environmental Innovations Chemist

• Two stationary phases optimized for PAH resolution.

• 3.5 minute EPA 610 and 6 minute EU PAH analyses by UHPLC.

• Portugal PAHs resolved by isocratic HPLC in 4 minutes.

Figure 1

Baseline resolve EPA 610 PAHs in less than 3.5 minutes on

1.9μm Pinnacle™ DB PAH columns.

Peak List:

1. naphthalene

2. acenaphthylene

3. 1-methylnaphthalene

4. 2-methylnaphthalene

5. acenaphthene

6. fluorene

7. phenanthrene

8. anthracene

9. fluoranthene

10. pyrene

11. benzo(a)anthracene

12. chrysene

13. benzo(b)fluoranthene

14. benzo(k)fluoranthene

15. benzo(a)pyrene

16. dibenzo(a,h)anthracene

17. benzo(ghi)perylene

18. indeno(1,2,3-cd)pyrene

Sample:

Inj.:

2µL

Conc.:

20µg/mL each component

Sample diluent: acetonitrile

Column:

Pinnacle™ DB PAH

Cat.#:

9470252

Dimensions:

50mm x 2.1mm

Particle size:

1.9µm

Pore size:

140Å

Instrument:

JASCO X-LC

Conditions:

Mobile phase:

A: water

B: acetonitrile

Time (min.) %B

100

Flow:

0.6mL/min.

Temp.:

30°C

Det.:

UV @ 264nm

LC_EV0469

min.

Compare to 5 min.

competitor analysis!