Restek Corporation • (800) 356-1688 • (814) 353-1300 •
attempt to determine the reason a reagent would be added to a
mobile phase, but any change ormodification should have an estab-
lished scientific purpose. By creatingmore universalmethods for
analyses of structurally related compounds, it should be possible to
reduce inventory costs for supplies, increase laboratory analysis effi-
ciency, and reduce personnel training time.
SeparationofNarcoticAnalgesics andAcetaminophen
onUltraC18.
Application 5
PeakList:
Conc.
(µg/mL)
Ret. Time
(min.)
Tailing Resolution
U.unknown
unknown
3.0
NA NA
1.morphine sulfate
204
3.3
0.97
2.3
2.acetaminophen
92
5.0
1.1
14.9
3.codeine phosphate
216
5.3
1.8
2.1
4.oxycodoneHCl
206
7.3
1.9
6.9
5.hydrocodone bitartrate 218
8.8
1.9
4.1
Sample:
Inj.:
10µL
Sample:
rawmaterial mix
Solvent:
mobile phase
LC_0219
Column:
UltraC18
Catalog #:
9174575
Dimensions: 250 x 4.6mm
Particle size: 5µm
Pore size:
100Å
Conditions:
Mobile Phase: A: pH 2.8 10mm
potassium
phosphate
B: acetonitrile
(85A:15B, v/v)
Flow:
1.0mL/min.
Temp.:
27°C
Det.:
UV@ 235nm
A small (5%) increase in the aqueous buffer doubles
resolution and retention.
Application 6
PeakList:
Conc.
(µg/mL)
Ret. Time
(min.)
Tailing Resolution
1.morphine sulfate
204
3.3
1.2
NA
2.acetaminophen
92
5.0
1.1
15.0
3.codeine phosphate
216
5.3
1.7
11.3
4.oxycodoneHCl
206
7.3
1.5
11.0
5.hydrocodone bitartrate 218
8.8
1.5
7.0
Sample:
Inj.:
4.0µL
Sample:
rawmaterial mix
Solvent:
mobile phase
LC_0220
Column:
UltraC18
Catalog #:
9174575
Dimensions: 250 x 4.6mm
Particle size: 5µm
Pore size:
100Å
Conditions:
Mobile Phase: A: pH 2.8 10mm
potassium phosphate
B: acetonitrile
(90A:10B, v/v)
Flow:
1.0mL/min
Temp.:
27°C
Det.:
UV@ 235nm
Further alteration of the organic phase improves resolution
without increasing analysis time.
Application 7
PeakList:
Conc.
(µg/mL)
Ret. Time
(min.)
Tailing Res.
U. unknown
unknown
3.0
NA NA
1. morphine sulfate
204
3.2
0.90 1.9
2. acetaminophen
92
4.8
1.1 12.2
3. codeine phosphate
216
5.1
1.4
2.3
4. oxycodoneHCl
206
6.9
1.4
8.2
5. hydrocodone bitartrate 218
8.0
1.4
4.8
Sample:
Inj.:
4.0µL
Sample:
rawmaterial mix
Solvent:
mobile phase
LC_0221
Column:
UltraC18
Catalog #:
9174575
Dimensions: 250 x 4.6mm
Particle size: 5µm
Pore size:
100Å
Conditions:
Mobile phase:A:pH 2.8 10mm
potassium phosphate
B:acetonitrile:methanol,
(90:10,v/v)
(85A:15B, v/v)
Flow:
1.0mL/min.
Temp.:
35°C
Det.:
UV@ 235nm
Application 8
Some analystsmay have neither the time nor the experience to trou-
bleshoot a problemmethodology. If you encounter problemswhen
analyzing your samples according to an establishedmethod, our
experiencedTechnical Service chemistswill be glad to help.
Contact them at 800-356-1688, ext. 4 or 814-353-1300, ext. 4, or
contact your Restek representative.
Increasing column temperature has detrimental effects on
the chromatography of narcotic / acetaminophen admixtures.
PeakList:
Conc.
(µg/mL)
Ret. Time
(min.)
Tailing Resolution
U.unknown
unknown
3.1
NA
NA
1.morphine sulfate
204
3.3
1.0
1.8
2.acetaminophen
92
5.0
1.1
14.1
3.codeine phosphate
216
5.5
1.4
2.6
4.oxycodoneHCl
206
7.5
1.4
8.5
5.hydrocodone bitartrate 218
8.9
1.4
5.0
Sample:
Inj.:
4.0µL
Sample: rawmaterial mix
Solvent: mobile phase
LC_0218
Column:
UltraC18
Catalog #:
9174575
Dimensions: 250 x 4.6mm
Particle size: 5µm
Pore size:
100Å
Conditions:
Mobile phase: A:pH 2.8 10mm
potassium phosphate
B: acetonitrile:methanol
(85A:15B, v/v)
Flow:
1.0mL/min.
Temp.:
27°C
Det.:
UV@235nm
