ENVIRONMENTAL ANALYSIS I. Solid Phase Extraction carbon-based sorbents

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