Strength in Technology…Strength in Technology…
Ken Butchart, Sandra Hanson. • Fortis Technologies Ltd, 45 Coalbrookdale Road, Cheshire, CH64 3UG, UK
Evaluation of HPLC Stationary Phases for Environmental Analysis
IntroductionIn environmental monitoring there are many compounds which have similarstructure and this can make the analysis of pollutants difficult to achieve in asimple cost effective way.Chromatography provides the option to gain resolution and sensitivity of manyenvironmental compounds in a short time, the use of UV detection or morecommonly Mass Spectrometer detection provides accurate and rapidconfirmation.
Pesticides, Polyaromatic Hydrocarbons (PAHs), PhenoxyHerbicides, Aldehydesand Explosives all present a challenge in the diversity of structures, requiredmobile phases and stationary phase choice. This means that a wide range ofchromatographic techniques must be utilised in order to gain the resolutionrequired.
Here we present data on a variety of applications and highlight whereimprovements in current methodology have been made.
Improving Transition IdentificationBy selecting the correct stationary phase for the analysis of both polar and non-polar compounds, resolution can be improved due to the sharp peak shapes andimproved retention..
FortisTM, is a trademarks of Fortis Technologies Ltd
Fortis Technologies Ltd recognises the trademarks of all other manufacturers
Atlantis ® is a registered trademark of Waters Corporation
Shim-pack® is a registered trademark of Shimadzu
All columns are original manufacturers packed columns
ConclusionBy selection of correct stationary phase coupled with UHPLC technology we areable to improve compound identification in several environmental applicationswhilst also significantly reducing analysis time.
Application of UHPLC to Reduce Analysis Times
Mobile phase A = aq 10 mM ammonium acetate
Mobile phase B = methanol
FIGURE 1. Analysis of 135 Pesticide Transitions – Apple Matrix
2 4 6 8 10 12 14 16 18 20 22 24 26Time, min
0.0
2.0e4
4.0e4
6.0e4
8.0e4
1.0e5
1.2e5
1.4e5
1.6e5
1.8e5
2.0e5
2.2e5
2.4e5
2.6e5
2.8e5
3.0e5
3.2e5
3.4e5
3.6e5
3.8e5
4.0e5
4.2e5
4.4e5
4.6e54.8e5
3.32
7.74
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24Time, min
0.0
5.0e4
1.0e5
1.5e5
2.0e5
2.5e5
3.0e5
3.5e5
4.0e5
4.5e5
5.0e5
5.5e5
6.0e5
3.16
7.696.064.822.85
10.0 10.5 11.0 11.5 12.0 12.5 13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0Time, min
0
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
2400
2600
2800
3000
3200
3400
3600
3800
13.20
13.5811.79
10.5 11.0 11.5 12.0 12.5 13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0Time, min
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
5500
13.23
13.52
Thaibendazole 0.9% Column carryover FortisTM C18, 150x2.1mm, 3um
Thaibendazole 1.9% Column carryover Atlantis® d C18, 150x2.1mm, 3um
FIGURE 4. PAH Analysis
NaphthaleneAcenaphthyleneAcenaphthaleneFluorenePhenanthreneAnthraceneFluoranthenePyreneBenz[a]anthraceneChryseneBenzo[b]fluorantheneBenzo[k]fluorantheneBenzo[a]pyreneDibeno[a,b]anthraceneBenzo[ghi]peryleneIndeno[1,2,3,cd]pyrene
Shimadzu LC-20AA: WaterB: ACNTime %B0 7020 7027 10030 7040 70
1.0ml/min40oC254nm
Shimpack VP-ODS 250x4.6mm 5um Fortis C18 50x2.1mm, 1.7um
35 min 3 min
FIGURE 3. Increased speed of Aldehyde Analysis
Conventional AnalysisShim-pack VP-ODS 250x4.6mm, 5um
Fast AnalysisFortis C18 50x2.1mm, 1.7um
FormaldehydeAcetaldehydeAcetoneAcroleinPropionaldehydeCrotonaldehydeButyraldehydeBenzaldehydeIsovaleraldehydeValeraldehydeo-Tolualdehydem,p-TolualdehydeHexaaldehyde2,5-Dimethylbenzaldehyde
Figure 1. Shows how the analysis of 105 pesticide compounds in 135 transitionsis achievable, the Fortis column providing greater no. of identifications whilst alsohaving less sample column carryover.
As well as improving compound identification selection of the correct UHPLCcolumn technology allows the analyst to reduce run times whilst improving peakresolution. Figure 3 shows the analysis time of 14 aldehydes successfullyreduced from 20 to 4 minutes.
Failure to meet maximum exposure limits imposed by many Food agencies canprove a barrier to trade, therefore accurate measurement of pesticide levels inagricultural products is important. Figure 2 shows that selection of a sub 2umparticle size can increase number of resolved peaks even when using a shortercolumn length – thereby generating less column backpressure and wear on thesystem.
Fortis C1830x2.1mm 1.7um
FIGURE 2. KFDA 83 59 Shim-pack® VP-ODS 150x2.1mm 2.2um
Fortis C1850x2.1mm 1.7um
A: Water/THF/MeOH 7/2/1
B: Water/ACN 4/6
Time %B
0 50
0.5 50
4 90
5 50
Flow: 0.4ml/min
Temp: 50oC
UV: 360nm
Phenoxy AcidsExplosives
Column: 1.7um Fortis Cyano, 50x2.1mm
Mobile Phase: 80/15/5 H2O/MeOH/ACN
Wavelength: 254nm
Flow rate: 0.2ml/min
Temperature: 50C
Column: 1.7um Fortis Cyano, 50x2.1mm
Mobile Phase: 80/20 H2O + 0.2% Acetic acid/ACN
Wavelength: 280nm
Flow rate: 0.2ml/min
Temperature: 25C
2.5mins14mins
FIGURE 5. Making Use of Alternate Selectivity
0.67
71.
2037
444
1.47
00.
7433
024
1.77
01.
34
2.00
01.
580
3.01
31.
0221
8298
3.21
71.
2433
6504
4.62
8
0.85
1936
71
5.24
2
5.85
80.
9126
0620
6.21
01.
0927
2054
6.75
3
7.53
50.
9425
0183
12.9
800.
00
0.00
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