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ENVIRONMENTALENVIRONMENTALANALYSISANALYSISI. Solid Phase ExtractionI. Solid Phase Extraction
ENVIRONMENTALENVIRONMENTALANALYSISANALYSISI. Solid Phase ExtractionI. Solid Phase Extraction
carbon-based sorbents
Graphitized Carbon BlacksGraphitized Carbon BlacksGraphitized Carbon BlacksGraphitized Carbon Blacks
120/400 mesh Non-porous Easy, Rapid Flow
100 m2/g Surface Area High Capacity
GC Stationary Phases Sorbent Surface
Contaminated w. oxygen complexes
MRM for PesticidesMRM for PesticidesMRM for PesticidesMRM for Pesticides
Pesticide classes1. Carbamates
2. Phenylureas
3. Triazines
4. Acetanilides
5. Phorphorothioates
6. Phenols
7. Phenoxyacids
Analytical method: HPLC
Extraction of PesticidesExtraction of PesticidesExtraction of PesticidesExtraction of Pesticides
Sample pre-treatmentSample pre-treatment
Column conditioningColumn conditioning
Column equilibrationColumn equilibration
Sample applicationSample application
0.4g/L Na-sulfite0.4g/L Na-sulfite
5mL MeCl/MeOH (4:1)5mL MeCl/MeOH (4:1)
2mL MeOH2mL MeOH15mL of 10g/L ascorbic acid15mL of 10g/L ascorbic acidin HCl-acidified water (pH 2)in HCl-acidified water (pH 2)
150 mL/min150 mL/min
Extraction of Pesticides (cont.)Extraction of Pesticides (cont.)Extraction of Pesticides (cont.)Extraction of Pesticides (cont.)
Interference elutionInterference elution
Analyte elutionAnalyte elution
7mL water, 7mL water, 1 1 min Nmin N2 2 or COor CO22
A: base/neutralsA: base/neutrals1 ml MeOH1 ml MeOH6 mL MeCl/MeOH (4:1)6 mL MeCl/MeOH (4:1)
B: acidsB: acids 6 mL MeCl/MeOH (3:2)6 mL MeCl/MeOH (3:2)
+ 16mM KOH+ 16mM KOH
Recovery of B/N PesticidesRecovery of B/N PesticidesRecovery of B/N PesticidesRecovery of B/N Pesticides
ether/nC61:1
pEther/To67:33
MeCl/ACN3:2
MeCl/MeOH4:1 MeCl
Methomyl 92 93 91 98 91
Metoxuron <5 <5 13 96 30
Atrazine 41 90 98 98 97
Propachlor 93 92 94 97 93
ParathionEt 65 70 95 92 91
GCB vs. C18 ExtractionGCB vs. C18 ExtractionGCB vs. C18 ExtractionGCB vs. C18 Extraction
GCB C18
1L 2L 4L 2L
Methomyl 99 98 86 4
Metoxuron 95 97 98 64
Atrazine 96 97 97 96
Propachlor 94 95 94 92
Parathion-Et 98 96 102 97Dinitro-o-Cresol 99 97 98 10
2,4-D 95 93 96 41