USP L9 column: SCX on silica
Fully porous silica of 3-10 um carrying a bonded strongly acidic (sulfonic) cation-exchange coating.
Mode: ion-exchange Typical pH range: about 2-7
Typical uses
- Cation-exchange separation of basic drugs and amines
- Some vitamin and amino compound assays
Common sizes (length x internal diameter, particle size)
- 250 x 4.6 mm, 5 um
- 150 x 4.6 mm, 5 um
Retention depends strongly on buffer ionic strength and pH.
Example columns sold as USP L9
From the makers' own USP code lists and product pages, checked October 2026. Examples only, not an endorsement. Columns with the same code can still differ in selectivity; if the monograph names a column in its notes, start with that one.
| Maker | Product family | Particle | pH range |
|---|---|---|---|
| Phenomenex | Luna SCX | fully porous silica 5/10 um | 2-7 |
| Waters | Spherisorb SCX | fully porous silica 5/10 um | not stated in source |
| Merck (Supelco) | SUPELCOSIL LC-SCX | fully porous silica | not stated in source |
| Macherey-Nagel | NUCLEOSIL SA | fully porous silica | not stated in source |
| Welch Materials | Ultisil XB-SCX | fully porous silica | not stated in source |
5 makers listed, so a tender written by USP code stays open to competition.
Tender wording (brand-neutral)
HPLC column with USP L9 packing (SCX on silica), 250 x 4.6 mm, 5 um (length x internal diameter, particle size); stainless-steel or equivalent hardware with standard fittings; recommended pH and temperature range to be stated by the bidder; each column supplied with its certificate of analysis and test chromatogram, batch/lot number and serial number; shelf life not less than 2 years from delivery; any make meeting the USP L9 designation and the stated dimensions is acceptable.
Size:
Changing length or particle size
You can keep the USP L9 packing and use a different length, particle size or diameter within the harmonized USP 621 limits. Check your columns with the calculator.
Related column types
L14 SAX on silica | L17 SCX resin, H+ form (organic acid / ion-exclusion) | L19 SCX resin, Ca2+ form (sugars) | L22 Cation-exchange polystyrene gel (sulfonic) | L23 SAX polymethacrylate/polyacrylate gel | L34 SCX resin, Pb2+ form (sugar alcohols) | L46 SAX, latex-agglomerated PS-DVB (9-11 um) | L52 SCX silica (sulfopropyl / sulfoethyl) | L53 WCX resin, carboxylic/phosphonic grafted EVB-DVB (cations IC) | L58 SCX resin, Na+ form (sugars/oligosaccharides)
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