IonPac CS14 Manual
Doc. No. 034848-10
Page 11 of 54
3.3.1 The 2-mm System Injection Loop, 2 - 15
μ
L
For most applications on a 2-mm analytical system, a 2–15 µL injection loop is sufficient. Dionex recommends that a 2.5 µL
injection loop be used to avoid overloading the CS14 2-mm Analytical Column. Generally, you should not inject more than 2.5
nanomoles (100–200 ppm) of any one analyte onto a 2-mm analytical column. Injecting larger volumes of samples can result in
overloading the column which can affect the detection linearity. The CS14 2-mm requires a microbore HPLC system
configuration. Install an injection loop one-fourth or less (< 15 µL) of the loop volume used with a 4-mm analytical system
(Section 2, “Comparison of 2-mm and 4-mm Ion Chromatography Systems”).
3.3.2 The 4-mm System Injection Loop, 10 - 50
μ
L
For most applications on a 4-mm analytical system, a 10–50 µL injection loop will be sufficient. Dionex recommends that a 10
µL injection loop be used to avoid overloading the CS14 4-mm Analytical Column. Generally, do not inject more than 10
nanomoles (100–200 ppm) of any one analyte onto the 4-mm analytical column. Injecting larger volumes of samples can result
in overloading the column which can affect the detection linearity. This phenomenon will be more prevalent at higher
concentrations of the analytes of interest.
3.4
Sample Concentration
The Trace Cation Concentrator (TCC-LP1, P/N 046027) or the IonPac CG14 4-mm Guard Column should be used for trace
cation concentration work on 4-mm systems. The TCC-LP1 or the IonPac CG14 2-mm Guard Column must be used for trace
cation concentrator work on 2-mm systems. See Section 4.5, “Sample Concentration,” for details on sample concentration.
3.5
IonPac CG14 Guard Columns
An IonPac CG14 Guard Column is normally used with the IonPac CS14 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. For maximum life of the analytical column, the guard column should be changed
or replaced as part of a regular maintenance schedule or at the first sign of performance deterioration. Use the test
chromatogram that is shipped with the analytical column or the initial application run for a performance benchmark.
3.6
Eluent Storage
IonPac CS14 columns are designed to be used with sulfuric acid or methanesulfonic acid (MSA) eluents. Storage under a
helium atmosphere ensures contamination free operation and proper pump performance (nitrogen can be used on 4-mm
systems if eluents do not contain solvents).
3.7
Cation Self-Regenerating Suppressor Requirements
A Cation Self-Regenerating Suppressor should be used for applications that require suppressed conductivity detection. It is
compatible with solvent containing eluents and aqueous ionic eluents of all concentrations with which the systems and
columns are compatible. Aqueous ionic eluents can be used in all CSRS ULTRA modes of operation.
Solvent containing eluents should be used in the AutoSuppression
™
External Water Mode.
If you are installing an IonPac CS14 4-mm Analytical Column, use a CSRS ULTRA (4-mm, P/N 043190).
CAUTION
