IonPac CS14 Manual
Doc. No. 034848-10
Page 31 of 54
5.13 Gradient Elution of Alkylamines, Ammonia, Group I & II Cations
The determination of many alkylamines in the presence of ammonia, Group I & II cations can be accomplished by gradient
elution in which methanesulfonic acid varies from 5 mM to 20 mM and the acetonitrile varies from 2.5% to 8%. Note that in
gradient analyses, increasing levels of ionic strength will increase baseline conductivity, while increasing levels of solvent will
decrease baseline conductivity.
Sample Loop Volume:
6.25 µL (2-mm), 25 µL (4-mm)
Analytical Column:
IonPac CS14 Analytical Column
Eluent:
See Gradient Program listed below
Eluent Flow Rate:
0.25 mL/min (2-mm), 1.0 mL/min (4-mm)
SRS Suppressor:
Cation Self-Regenerating Suppressor, CSRS ULTRA (2-mm or 4-mm)
External Water Mode
or MMS Suppressor:
Cation MicroMembrane Suppressor, CMMS III (2-mm or 4-mm)
MMS Regenerant:
100 mN TBAOH
(tetrabutylammonium hydroxide)
Expected Background Conductivity:
< 1 µS
Storage Solution:
Eluent
Eluent 1:
Type I DI Water
Eluent Flow Rate:
1.0 mL/min
Eluent 2:
100 mM MSA
(4-mm System)
Eluent 3:
10% Acetonitrile
Eluent 4:
100% Acetonitrile
TIME (min)
%E1
%E2
%E3
%E4
Comments
Equilibration
0.0
70
5
25
0
Equilibrate to 5.0 mM MSA / 2.5% ACN
10.0
70
5
25
0
Analysis
0.0
70
5
25
0
Inject, 5.0 mM MSA / 2.5% ACN
0.1
70
5
25
0
Inject Valve to Load Position
7.0
69
6
25
0
6.0 mM MSA / 2.5% ACN
12.0
62
13
25
0
13.0 mM MSA / 2.5% ACN
16.0
0
20
80
0
20.0 mM MSA / 8.0% ACN
18.0
0
20
80
0
20.0 mM MSA / 8.0% ACN
22.0
30
35
0
35
35.0 mM MSA / 35% ACN
25.0
30
35
0
35
35.0 mM MSA / 35% ACN
25.1
70
5
25
0
5.0 mM MSA / 2.5% ACN
