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FAQ

A. HPLC Columns

1. How should Shodex columns be stored?

In general, Shodex recommends storing the columns in the shipping solvent at ambient temperature (avoid significant temperature fluctuation), if not otherwise stated in the column manual. The shipping solvent is mentioned in the column manual.

2. When and how should Shodex columns be cleaned?

When the separation performance of the column is decreased, e.g. visualized by the shift of retention times and/or peak deformation, the column may be regenerated by certain washing procedures. In most cases the column cleaning procedures can be found in the column manual or you can also download the overview of the column cleaning procedures in the download section on the Shodex website www.shodex.de. After registration you will have free access.

3. Where can I get column manuals for reprint?

Please register on the Shodex website www.shodex.de . In the download section you can find all columns manuals and you will be able to download them as PDF file.

4. Can I get spare parts for HPLC columns?

Shodex doesn’t provide any spare parts (e.g. nuts, frites, etc.) for HPLC columns. Especially, when the column has to be opened to exchange parts of the columns the separation performance cannot be guaranteed any more.

5. Are guard cartridges and holders available for Shodex columns?

Shodex is offering small complete columns which are used as guard columns. Therefore, there are no cartridges and holders available. An exception is the new GPC HK-G 6 GPC HK-G filter as a guard cartridge for GPC HK-404 L.

6. How should the guard column and the main column be connected?

The guard column and the main column can be easily connected by fittings and capillaries. Please avoid too long capillaries or capillaries with big inner diameter which can create in addition a certain dead volume.

7. Does Shodex offer UHPLC columns for reversed phase chromatography?

Shodex is not offering UHPLC columns for reversed phase chromatography.

8. Which further solvents can be used for Shodex GPC columns?

Please take a look at the solvent replacement table which can be found in the download section on the Shodex website www.shodex.de . You will have free access after registration.

9. How long Shodex columns should be equilibrated?

In general, the equilibration time depends on the separation technique. E.g. for our HILIC columns, an equilibration of 10 to 15 column volumes is recommended.

10. What is the lifetime of polymeric columns?

Compared to silica-based columns, polymeric columns can show a 2 to 3 times longer lifetime. Please be aware that in general the lifetime highly depends on the sample/sample matrix. Therefore, a certain number of injections cannot be guaranteed.

11. How can I transfer the loading capacity and/or injection volume from one column size to another?

There is a direct correlation between the injection volume as well as the loading capacity and the cross sectional area, which can be described by A = πr2, and length of the column. Therefore, in the case a certain method was already established on e.g. an analytical column with 4.6 mm inner diameter and should be transferred to bigger column with 8.0 mm inner diameter with same length, the loading capacity would increase by approximately a factor of 3.

 

B. SEC Calibration Standards

1. Which calibration standards does Shodex offer?

Shodex offers three different standards for size exclusion chromatography, Pullulan (unbranched polysaccharide for applications in aqueous eluents), Polystyrene (PS) and Polymethylmethacrylate (PMMA) (polymers for applications in organic solvents).