IonPac NS1 Manual
Document No. 034024-06
Page 7 of 35
On the next day, prior to the use of the chromatographic system, rinse the IonPac Trap Column. This will help with equilibration
times.
A. Rinse the TC-1 with 30 mL of the strongest eluent used in the gradient analysis.
B. Reconnect the IonPac Trap Column, after flushing it with eluent, to the eluent line that is connected to the injection
valve.
2.4
The IonPac NG1 Guard Column
An IonPac NG1 Guard Column is normally used with the IonPac NS1 analytical column. Retention times will increase by
approximately 20% when a guard column is placed in-line prior to the analytical column. A guard is placed prior to the analytical
column to prevent sample contaminants from eluting onto the analytical column. It is easier to clean or replace a guard column than
it is an analytical column. Replacing the NG1 Guard Column at the first sign of peak efficiency loss or decreased retention time
will prolong the life of the NS1 analytical column.
2.5
Eluent Storage
IonPac NS1 columns are designed to be used with Tetrabutylammonium hydroxide eluent systems. Storage under a helium
atmosphere ensures contamination free operation and proper pump performance (nitrogen can be used if eluents do not contain
solvents).
2.6
Anion Self-Regenerating Suppressor Requirements
The Anion Self-Regenerating Suppressor (ASRS ULTRA II) is used for eluent suppression of MPIC (ion-pairing) eluents by using
the MPIC Suppression Mode of operation. This suppression mode is a combination of the AutoSuppression External Water Mode
augmented with a chemical regenerant such as sulfuric acid (H
2
SO
4
). The MPIC Suppression Mode uses an applied current and
a constant source of dilute sulfuric acid solution delivered from an AutoRegen Accessory or a pressurized bottle system. The MPIC
Suppression Mode reliably provides suppression of typical eluents for MPIC applications using suppressed conductivity detection.
The ion pair reagents, such as tetrabutylammonium hydroxide (TBAOH), are used in concentrations ranging typically from 1.0
to 5.0 mM. For detailed information on the operation of the ASRS ULTRA II, see Document No. 031956.
The Cation Self-Regenerating Suppressor (CSRS ULTRA II) can be used for suppression of MPIC (ion-pairing) eluents by using
the AutoSuppression External Water Mode of operation or the MPIC Suppression Mode depending on the specific MPIC
application. The MPIC Suppression Mode is a combination of the AutoSuppression External Water Mode augmented with a
chemical regenerant if necessary such as boric acid (H
3
BO
3
). When the CSRS ULTRA II is operating in this mode, it uses an applied
current and a constant source of dilute boric acid solution delivered from a pressurized bottle system. For detailed information on
the operation of the CSRS ULTRA II, see Document No. 031956.
An Anion or Cation Self-Regenerating Suppressor should be used for ion pairing applications that require suppressed conductivity
detection. The ASRS ULTRA II in the MPIC Suppression Mode of operation and the CSRS ULTRA II in the AutoSuppression
External Water or MPIC Suppression Mode of operation are compatible with aqueous ionic eluents of all concentrations with which
the column and system are compatible and with solvent containing eluents up to 40% by volume. For applications requiring solvent
above 40% by volume, the Chemical Suppression Mode of operation must be used. Aqueous ionic eluents can be used in all modes
of operation.
NOTE
When using eluents containing solvent above 40% by volume, the ASRS ULTRA II or CSRS ULTRA II should
be used in the Chemical Suppression Mode.
If you are installing an IonPac NS1 4-mm analytical column for ion pairing chromatography with suppressed conductivity
detection, use an ASRS ULTRA II, 4-mm, (P/N 061561) for Anion-MPIC
or the CSRS ULTRA II, 4-mm, (P/N 061563) for Cation-
MPIC.
The AMMS-ICE II (P/N 037107) is used with Ion Exclusion and Ion Suppression Modes of Ion Chromatography. For detailed
information on the operation of the AMMS-ICE II, see Document No. 032661.
