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2,4-Dichlorophenoxyacetic Acid in Water
Using 500mg 6mL HyperSep Retain PEP Extraction Column
(Part Number: 60107-206)
Sample Preparation
Adjust the pH of 500mL of water to 1.5 to 2 using
0.5 M H
2
SO
4
Condition Retain PEP Extraction Column
3mL of tetrahydrofuran
5mL of methanol
5mL of DI H
2
O
Apply Sample
Load the 500mL sample at a rate no greater than
5mL/min
Wash Column
5mL of DI H
2
O
Dry column (20 minutes at >10"Hg/full flow for positive
pressure manifold)
Elute 2,4-Dichlorophenoxyacetic Acid
Use 0.8mL of methanol to replace the residual water in
the PEP packing
Discard the water which passes through the SPE column
Wait for 2 minutes to make sure the methanol infiltrates
the packing material
Elute the column with 3mL of THF
Collect the eluate and reconstitute to 3mL using
mobile phase
EPA Method 508 – Analysis of Chlorinated Pesticides,
Herbicides and Organohalides
Using 10g 75mL HyperSep C18 Extraction Column
(Part Number: 60108-703)
Sample Preparation
1L water collected
Add MgCl
2
(final conc. 10mg/L)
Condition HyperSep C18 Extraction Column
1 x 1mL 1:1 EtAc/CH
3
Cl
2
1 x 10mL CH
3
OH
1 x 10mL H
2
O
Apply Sample
Add 1 x 5mL CH
3
OH to sample
Mix
Take 50µL of sample and mix
Load sample at 1 to 2mL/minute
Elute
Insert fresh collection tubes into manifold
1 x 10mL EtAc
1 x 10mL CH
3
Cl
2
1 x 3mL EtAc/CH
3
Cl
2
Evaporation
Evaporate eluates to 0.8mL under a gentle stream of
nitrogen in a heated water bath 40°C
Add internal standard
Adjust volume to 1mL
Analysis
Add 1 to 2µL onto GC
Recommended GC Column
Part Number
TraceGOLD TG-OCP I 30m x 0.25m x 0.25µm
26078-1420
Environmental
Applications