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2007 vol. 2
Environmental
Separate Explosives and Propellant Residues
Using Ultra C18 and Pinnacle™ II Biphenyl Columns
by Robert Freeman, Environmental Innovations Chemist
• Easily quantify and confirm new US EPA
Method 8330B target analytes.
• Excellent resolution, improved accuracy.
• Simple, easy to use, isocratic method.
US EPA 8330, a test method for determining trace
amounts of 14 nitramines and nitrate esters, was
recently revised to include three new target ana-
lytes. The new method, EPA 8330B, includes nitro-
glycerin (NG), pentaerythritol tetranitrate, (PETN),
and 3,5-dinitroaniline (3,5-DNA) and now covers
17 analytes that are commonly found in explosives
and propellants residues. This method uses reversed
phase HPLC and dual wavelength UV detection
(210 & 254nm) in conjunction with a primary and
a confirmation column.
We recently assessed the performance of our current
column offerings relative to the elution order and
retention times of the new analytes in the revised
method. Separations on all columns were accom-
plished using a simple, isocratic water:methanol
mobile phase (Table 1). The primary and confir-
mation columns that we recommend for the EPA
8330 analysis are the Ultra C18 and Pinnacle
™
II
Biphenyl columns, respectively. Based on this work,
we conclude this combination will work well for
the revised method, EPA 8330B, as shown by the
chromatograms in Figures 1 and 2. Both columns
provide excellent resolution of the EPA 8330B ana-
lytes and their differing selectivity provides a true
confirmation analysis.
As an alternative to the Ultra C18/Pinnacle™ II
Biphenyl combination, a Pinnacle™ II C18 column
and a Pinnacle™ II Cyano column work well together
as a primary-confirmation column set. Another
column of interest is the Allure® Biphenyl column.
A high organic mobile phase was required on this
column but the analysis was completed in approx-
imately six minutes (Table 1).
Figure 1
Excellent resolution of EPA 8330B target analytes on the
Ultra C18 column.
Figure 2
Alternate selectivity of EPA 8330B analytes on the
Pinnacle™ II Biphenyl column confirms compound identity.
LC_EV0428
LC_EV0429
Sample:
50μg/mL each compound diluted in acetonitrile
8330 Calibration Mix #1 (cat.# 31450)
8330 Calibration Mix #2 (cat.# 31451)
PETN Standard(cat.# 31600)
3,5-dinitroaniline Reference Mix (cat.# 31661)
Nitroglycerin Reference Mix (cat.# 31498)
Inj.:
10μL
Column:
Ultra C18
Cat.#:
9174575
Dimensions:
250mm x 4.6mm
Particle size:
5μm
Pore size:
100Å
Conditions:
Mobile phase:
water:methanol
(44:56 v/v)
Flow:
1.0mL/min.
Temp.:
30°C
Det.:
UV detection @ 210nm
Sample:
50μg/mL each compound diluted in acetonitrile
8330 Calibration Mix #1 (cat.# 31450)
8330 Calibration Mix #2 (cat.# 31451)
PETN Standard (cat.# 31600)
3,5-dinitroaniline Reference Mix (cat.# 31661)
Nitroglycerin Reference Mix (cat.# 31498)
Inj.:
10μL
Column:
Pinnacle
™
II Biphenyl
Cat.#:
9209565-700
Dimensions:
250mm x 4.6mm
Particle size:
5μm
Pore size:
110Å
Conditions:
Mobile phase:
water:methanol
(44:55 v/v)
Flow:
1.2mL/min.
Temp.:
30°C
Det.:
UV detection @ 210nm
Peak List
1. HMX
2. RDX
3. 1,3,5-TNB
4. 1,3-DNB
5. 3,5-DNA
6. NB
7. tetryl
8. 2,4,6-TNT
9. NG
Peak List
10. 2-A-4,6-DNT
11. 4-A-2,6-DNT
12. 2,4-DNT
13. 2,6-DNT
14. 2-NT
15. 4-NT
16. 3-NT
17. PETN
1
2
9
5
6
11
10
4
14
16,15
13
3
12 7
8
17
Peak List
1. HMX
2. RDX
3. 1,3,5-TNB
4. 1,3-DNB
5. 3,5-DNA
6. NB
7. tetryl
8. 2,4,6-TNT
9. NG
Peak List
10. 2-A-4,6-DNT
11. 4-A-2,6-DNT
12. 2,4-DNT
13. 2,6-DNT
14. 2-NT
15. 4-NT
16. 3-NT
17. PETN