Why Are There so Many C18 LC Columns?

From end-capped to aqueous, there are a multitude of C18 phases to choose from. But why are there so many? A C18 is a C18, right?
In today’s Restek Tip, we’re going to explore the world of C18 phases. Are there benefits to choosing one specific to your analysis? And what parameters should you keep in mind when selecting a phase?
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Additional Resources
A C18 is a C18, right? | www.restek.com/chromablograph...
Why do I Lose Retention on my C18 in High Aqueous Mobile Phases? | www.restek.com/articles/tech-...
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Restek Recommended Tools & Parts
Raptor C18 LC Columns (traditional, end-capped columns) | www.restek.com/search/analyti...
Ultra Aqueous C18 LC Columns (100% aqueous phase columns) | www.restek.com/search/analyti...
Raptor ARC-18 LC Columns (sterically-protected, acid resistant columns) | www.restek.com/search/analyti...
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[@alahamomand33]

I am studying for my Chromatography course and this video was literally so well made. Thank you!

[@kimyenle5483]

I want to get information about retention time requirement, peak width between LC and GC. Thanks very much

[@AnaCeciliaOliveira-kn1dn]

What's the difference between ODS and BDS C18?

[@melaniegwendolyn7005]

What is the difference between SB-C18 column and a typical C18 column? Does it affect the retention time of the desired analyte in both of the column?

[@RestekCorp]

SB-C18 is another manufacturer’s product that looks most similar to our ARC-18. Therefore, an SB-C18 or ARC-18 has bulky sidechains at the base of the ligand that help to protect the ligand from being cleaved by acidic compounds, making the column more acid stable. This also allows analytes to have greater access to the silica surface, as these faces are often not endcapped. This means that polar analytes often have greater affinity for these types of columns that traditional endcapped C18 columns. Both columns have their place and uses. SB-C18 literature reports they are stable down to pH1. Our ARC-18 column also offers the same pH range stability. While the other manufacturer doesn’t appear to disclose in their product literature the structure of their SB sidechain, we can share that our sidechains are isobutyl groups attached to the silicon atom.

[@yogeshchoudhari9429]

Which coloumn to be used for highly polar molecule??

[@RestekCorp]

We recently introduced a column specifically for highly polar analytes www.restek.com/technical-literature-library/articles/raptor-polar-x-separate-a-wide-variety-of-polar-analytes-with-a-novel-hybrid-stationary-phase/

[@vishnupatil1345]

carbon loading and carbon chain both same or different

[@RestekCorp]

They are different, but there is usually some correlation. Carbon chain refers to the number of carbons in an alkyl bonded phase, while carbon load refers to the percent, by weight, that is carbon. In general, longer carbon chains would produce higher carbon loads, but other factors can also influence the carbon load.