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Nitroanalines in Solution
Using 60mg 3mL HyperSep Retain PEP Extraction Column
(Part Number: 60107-203)
Sample Preparation
Prepare solutions of 2-nitroaniline and 4-nitroaniline
in 0.1% ammonia aqueous at concentrations of
20, 2 and 0.2ppm
Condition Retain PEP Extraction Column
3mL of methanol
3mL of DI H
2
O
Apply Sample
Load 3mL samples at 1 to 2mL/minute
Wash Column
1mL of 0.1% ammonia aqueous solution
Elute Nitroanalines
3mL of methanol/1% formic acid (95:5, v/v)
Dry Eluate and Reconstitute
Evaporate to full dryness at room temperature under a
stream of nitrogen
Reconstitute the sample to 1mL with methanol
Analysis
Mobile phase: methanol/1% formic acid (10:90, v/v)
Recommended HPLC Column
Part Number
Hypersil GOLD aQ 5µm, 250 x 4.6mm
25305-254630
Results
Sample 4-nitroaniline
Concentration (ppm)
Peak Area (av) std
Peak Area (av) Retain PEP
Recovery (%) Retain PEP
a
20
296740.5
270652
91
b
2
28374.5
31517
111
c
0.2
2830.5
2947
104
Sample 2-nitroaniline
Concentration (ppm)
Peak Area (av) std
Peak Area (av) Retain PEP
Recovery (%) Retain PEP
a
20
464657.5
456445
98
b
2
45113.5
46537
103
c
0.2
3489.5
4234
121
Nitrobenzene in Water
Using 500mg 6mL HyperSep Retain PEP Extraction Column
(Part Number: 60107-206)
Sample Preparation
Ensure that a 497.5mL sample of water is pH neutral
To this sample, add 2.5mL of methanol
Condition Retain PEP Extraction Column
3mL of hexane
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 Nitrobenzene
Use 0.8mL of acetone 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 acetone infiltrates
the packing material
Connect the Retain PEP column to a column packed with
5g of anhydrous sodium sulphate which has been
washed with 3mL of acetone, 3mL of hexane and
3mL acetone
Elute the column series with 10mL of hexane/acetone
(90:10, v/v)
Collect the eluate and concentrate to 1mL with nitrogen
at 40°C
Environmental
Applications