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Which LC column should I use for my method?

13 Sep 2017

We understand that with so many products on the market, choosing a column to get started can be difficult. Of course, column selection depends on what type of method you are following and what kind of LC system you have in your lab. Let’s begin by looking at our choices for the more traditional, fully porous particle LC columns.

column in package

If your method is a USP or other compendial method, the preferred column would be one of our Roc HPLC columns. The ROC phase selections we offer encompass most of what you would need for these methods. The Roc columns are very appropriate for any highly regulated work environment where a rugged and long-lasting column is desired and lot to lot reproducibility is critical. Most regulations also allow for slight modifications in column dimensions, as well as other parameters for example, as indicated here in this document from the FDA: https://www.fda.gov/downloads/ScienceResearch/FieldScience/LaboratoryManual/UCM173085.pdf

If your method is not a USP method, but is very well established for a 3 or 5 µm particle column, simple in design, and requires very high reproducibility, the Roc HPLC columns are still preferred. If you find that the phase or dimensions you need are not offered as a Roc column, the next place to look would be within our Ultra columns. Ultra columns are also available in preparative sizes if you are doing purification work with large sample sizes.

If you have a challenging method that is written for UHPLC (<2.0 µm fully porous particles) or one that you would like to eventually convert to a UHPLC method, our new Force LC columns are the ideal product. We are excited to offer these columns made with the highest quality silica in a 1.8 µm particle size, as well as 3 and 5 µm for easy method transfer between HPLC and UHPLC systems. Force columns are available in C18, Biphenyl, and Fluorophenyl phases.

If your method requires an SPP (superficially porous particle) column or you are looking for superior separation and a fast analysis, but you do not have a UHPLC system, the Raptor columns are ideal. Raptor 2.7 µm columns are preferred for large analyte panels such as pesticides, steroids, and drugs, and are typically used with LC-MS/MS.

Raptor 5.0 µm columns won’t be able to separate quite as many analytes, but separation is still better than you would get with a fully porous 5.0 µm column. Often when using LC-MS/MS, less chromatographic separation is acceptable because the MS can identify closely eluting and even coeluting compounds, unless they are isobaric, so a 5.0 µm column is often still useful. Although it depends on the exact dimensions, generally speaking, the 2.7 µm columns are intended for use with LC systems that have a 600 bar (8700 psi) pressure limit, whereas the 5.0 µm columns are intended for those with a 400 bar (5800 psi) limit. Please see the blog post “Should I use a 2.7 or 5 µm Raptor column?” for more discussion of this.

To find a listing of all LC columns we offer, you might also find our LC Columns Physical Characteristics Chart useful.

I hope you have found this post helpful. Thank you for reading.