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IonPac NS1 Manual

Document No. 034024-06

Page 28 of 35

5.2.2 Contaminated Anion Trap Column, the ATC-3 (4-mm)

When doing gradient analysis, ensure that the Anion Trap Column, the ATC-3 (2-mm) or the ATC-3 (4-mm) has been
installed correctly.

 If it has not, install one as directed in Section 2.3, “The Anion Trap Column,” and watch the background

conductivity. If the background conductivity is now low, this means that the ATC is trapping contaminants from the eluent. The
eluents probably have too many impurities (see items A–C above).

Determine if the ATC is the source of high background conductivity.

 Remove the ATC. If the background conductivity remains

high, then the ATC is not the problem. If the background conductivity decreases, the ATC is the source of the high background
conductivity.

A. Disconnect either the ATC-3

 (4-mm) from the injection valve and direct the outlet to waste.

B. Flush the ATC with 200 mL of 35 mM NaOH or the highest NaOH concentration used in the application.

 Use

a flow rate of 2.0 mL/min on a 4-mm system.

C. Equilibrate the ATC with the strongest eluent used during the gradient run.

 Use a flow rate of 2.0 mL/min on a

4-mm system.

D. If the problem persists, replace the ATC.

5.2.3 Contaminated Guard or Analytical Column

Remove the IonPac NG1 Guard and IonPac NS1 analytical columns from the system. If the background conductivity decreases,
then one (or both) of these columns is (or are) the cause of the high background conductivity, clean the column as instructed in
Appendix B - Column Care.

5.2.4 Contaminated Hardware

To eliminate the hardware as the source of the high background conductivity, bypass the SRS suppressor and pump deionized water
with a specific resistance of 18.2 megohm-cm through the system. The background conductivity should be less than 2 µS. If it is
not, check the detector/conductivity cell calibration by injecting deionized water directly into it. See the appropriate manual for
details.

5.2.5 Contaminated  Suppressor

Assume that the SRS or the AMMS-ICE is causing the problem if the above items have been checked and the problem
persists.

A. Check the regenerant flow rate

 at the 

REGEN OUT

 port of the SRS or the AMMS-ICE. For the example isocratic

applications, this flow rate should be 3–5 mL/min in the Chemical Suppression Mode of operation.

B. Check the eluent flow rate.

 For most applications, the eluent flow rate for 2-mm applications should be 0.50 mL/min

and for 4-mm applications, it should be 2.0 mL/min. Refer to the Self-Regenerating Suppressor Product Manual
(Document No. 031956) or the Anion-II MicroMembrane Suppressor-ICE Product Manual (Document No. 032661)
to ensure that the eluent is within suppressible limits.

C. Test both the suppressor and the Anion AutoRegen Regenerant Cartridge for contamination

 if you are using an

AutoRegen Accessory with the ASRS ULTRA II (in the MPIC or Chemical Suppression Mode) or the CSRS (in the
Chemical Suppression Mode). Prepare fresh regenerant solution.

1. Clean or replace your SRS or AMMS-ICE if the background conductivity is high after preparing fresh

regenerant and bypassing the Anion AutoRegen Regenerant Cartridge.

 Refer to the “Self-Regenerating

Suppressor Product Manual” (Document No. 031956) or the “Anion-ICE MicroMembrane Suppressor II Product
Manual” (Document No. 032661) for assistance.

Содержание IONPAC NG1

Страница 1: ...eluent for the IonPac NS1 is 3 mM Tetrabutylammonium hydroxide 28 Acetonitrile See Section 3 4 Preparing Eluents with Solvents Make the required stock and working solutions for eluents See Section 3 O...

Страница 2: ...irements 9 3 3 1 Inorganic Chemicals 9 3 3 2 Deionized Water 9 3 3 3 Solvents 9 3 3 4 Acid Modifiers 10 3 3 5 Base Modifiers 10 3 4 Preparing Eluents that Contain Solvents 10 3 4 1 Eluents for Reverse...

Страница 3: ...2 3 Separation of Benzoic Acid and o nitrobenzoic Acid 23 4 2 4 Gradient Separation of Aliphatic Carboxylic Acids 24 SECTION 5 TROUBLESHOOTING 25 5 1 High Back Pressure 26 5 1 1 Finding the Source of...

Страница 4: ...eluent suppressor designed for use with ion exclusion and ion suppression separation modes of ion chromatography Many analytes of interest are neither ionizable nor UV detectable Organic and inorgani...

Страница 5: ...Back Pressure Flow Rate Flow Rate psi MPa mL min mL min NS1 Analytical 900 6 21 1 400 9 66 1 0 3 0 NG1 Guard 200 1 38 300 2 07 1 0 3 0 NS1 NG1 columns 1 100 7 59 1 700 11 73 1 0 3 0 NS1 5 m analytica...

Страница 6: ...192 The IonPac Trap Column should be installed in place of the high pressure gradient mixer between the gradient pump and the injection valve The IonPac Trap Column is filled with high capacity ion ex...

Страница 7: ...usingsuppressedconductivitydetection 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 op...

Страница 8: ...onPac NS1 Manual Document No 034024 06 Page 8 of 35 2 7 Detector Requirements See Section 2 Ion Chromatography System Operation Summary for 4 mm system detector cell and thermal stabilizer requirement...

Страница 9: ...er possible inorganic chemicals that meet or surpass the latest American Chemical Society standard for purity should be used These inorganic chemicals will detail the purity by having an actual lot an...

Страница 10: ...rength of the eluent and the flow rate used The column back pressure will vary as the composition of water methanol and water acetonitrile mixture varies The practical back pressure limit for the IonP...

Страница 11: ...nts Eluent A 10 solvent 90 water Eluent B 90 solvent 10 water Then by programming the gradient pump properly you can go from 100 Eluent A to 100 Eluent B in a prescribed time This will avoid outgassin...

Страница 12: ...ity to increase which can result in a noisy background Most solvents have no affect on the cartridge lifetime In all cases the ionic strength of the eluent determines the lifetime of the AutoRegen Reg...

Страница 13: ...ranteed high purity use Dionex Cation Regenerant Concentrate P N 039602 to make regenerant for the CSRS ULTRA II CAUTION Acetonitrile is not compatible with the CSRS ULTRA II in the Chemical Suppressi...

Страница 14: ...ese ion pair reagents can be anionic or cationic Here is a partial list of typical ion pair reagents A Cationic Tetramethyl ethyl propyl and butyl ammonium salts of the general form R R N R R Counter...

Страница 15: ...ng of the IonPac NS1 To guarantee that all IonPac NS1 analytical columns meet high quality and reproducible performance specification standards all columns undergo the following production control tes...

Страница 16: ...Detection and Solvent Ion pairing can separate monovalent anions such as chlorate and nitrate which differ in hydration energy Because ion pairing has low selectivity for higher valency ions selected...

Страница 17: ...furic acid regenerant Aliphatic sulfonic acids are UV transparent but well detected by suppressed conductivity Column IonPac NS1 10 m Eluent 2 mM Tetrabutylammoniumhydroxide 24 to 48 Acetonitrile in 1...

Страница 18: ...atic sulfonic acids Column IonPac NS1 10 m Eluent 2 mM Tetrabutylammonium hydroxide 24 to 48 Acetonitrile in 10 min Flow Rate 1 0 mL min Injection Loop 50 L Detection Suppressed conductivity ASRS ULTR...

Страница 19: ...nitrile increases a decrease in the background conductivity is observed Column IonPac NS1 10 m Eluent 2 mM Nonafluoropentanoic acid 20 to 80 Acetonitrile in 10 min Flow Rate 1 0 mL min Injection Loop...

Страница 20: ...rate counter ion displaces the hydroxide counter ion from the fully ionized alkali and alkaline earth metals which reduces the observed conductance for these ions Column IonPac NS1 10 m Eluent 2 mM No...

Страница 21: ...4 Basic molecules can be deprotonated at high pH s 9 O OH H Anionic R C O R C O pH 4 OH Cationic R NH3 R NH2 H2 0 pH 9 Ionic Neutral Additionally selectivity can be effected by working within one pH u...

Страница 22: ...uble Vitamins by Ion Suppression Ion Pair Chromatography Peaks 1 Ascorbic acid 2 Nicotinic acid 3 Nicotinamide 4 Riboflavin 5 Pyridoxine 6 PABA 7 Folic acid 8 Pyridoxamine 9 Thiamine 10 Cyanocobalamin...

Страница 23: ...acid 4 2 3 Separation of Benzoic Acid and o nitrobenzoic Acid Figure 9 Separation of Benzoic Acid and o Nitrobenzoic Acid Using Ion Suppression Chromatography BEFORE AFTER Eluent 3 mM HCl 32 Acetonit...

Страница 24: ...ydroxide Column IonPac NS1 Flow Rate 1 0 mL min Eluent 1 24 ACN 6 MeOH 0 03 mM HCl Eluent 2 60 ACN 24 MeOH 0 05 mM HCl Gradient 0 100 E2 in 20 min Temperature 42 C Detection Suppressed Conductivity AM...

Страница 25: ...dules Disconnect Replace System Module Manual High Background Conductivity Bad Eluents Remake Eluents 5 2 5 2 1 Contaminated Columns Clean Column 5 2 2 5 2 3 Contaminated ASRS or AMMS Clean Suppressor...

Страница 26: ...nstall two adaptor assemblies on the filter On the end of the filter with the 1 4 28 male fitting place a 1 4 28 to 10 32 union P N 042806 On the end of the filter with the 1 4 28 female port place a...

Страница 27: ...into the end fitting IonPac NS1 Column 4 mm Part P N Analytical Column 10 m 035321 Analytical Column 5 m 039568 Guard Column 039567 Bed Support Assembly 042955 End Fitting 052809 CAUTION If the column...

Страница 28: ...minatethehardwareasthesourceofthehighbackgroundconductivity bypasstheSRSsuppressorandpumpdeionizedwater with a specific resistance of 18 2 megohm cm through the system The background conductivity shou...

Страница 29: ...lumn must be replaced 5 3 2 Poor Resolution Due to Shortened Retention Times Even with adequate system and column efficiency resolution of peaks will be compromised if analytes elute too fast A Checkt...

Страница 30: ...n the system prior to the analytical column and test for front end resolution after every system change 5 4 Spurious Peaks A The column may be contaminated If the samples contain an appreciable level...

Страница 31: ...Regenerating Suppressor SRS to the detector conductivity cell at the suppressor end of the line C Install a 10 32 Luer adaptor fitting with a plastic syringe in the ELUENT OUT port of the Self Regene...

Страница 32: ...n Suppressed Conductivity ASRS ULTRA AutoSuppression External Water Mode with 10mN Sulfuric Acid Range 10 SFS Background Conductivity 3 15 S Injection Volume 10 L Peak Information Found Components Pea...

Страница 33: ...n Suppressed Conductivity ASRS ULTRA AutoSuppression External Water Mode with 10 mN Sulfuric Acid Range 10 SFS Background Conductivity 3 15 S Injection Volume 10 L Peak Information Found Components Pe...

Страница 34: ...lush the column for a minimum of 10 minutes with the storage solution Cap both ends securely using the plugs supplied with the column B 4 Column Cleanup The following column cleanup protocols have bee...

Страница 35: ...umn Cleanup Procedure A Prepare a 500 mL solution of the appropriate cleanup solution using the guidelines in Section B 4 1 Choosing the Appropriate Cleanup Solution B Disconnect the Suppressor from t...

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