Should your LC column temp be controlled?

You may not think temperature is critical for your LC columns, but check out our blog post here:

Don’t Overlook LC Column Temperature!

As discussed in the post, column temperature can impact peak shape, retention and backpressure. It can sometimes make the difference in whether certain analytes are resolved. Increasing the temperature speeds up the movement of analytes between the mobile phase and stationary phase. This results in shorter retention times and often also results in better peak shape. The exact effect is different for various analytes, but temperature is always worth considering when optimizing a method.

You may think that using a column at ambient temperature is fine, but consider what could happen when fluctuations occur. Often indoor climate-controlled buildings will fluctuate by 3 degrees or more, particularly if running overnight. A general rule of thumb for reversed phase LC is that for every degree (Celsius) that the temperature is increased, the retention time typically decreases about 2%1. Most concerning is the impact on retention time during a series of injections. This is mentioned in our blog post here:

Why is my LC Retention Time Shifting?

• Changes in column temperature- this can affect the column in a way similar to flow rate and can move the retention in either direction. Make sure you have the column in a thermostatic column compartment to avoid this.

Most LC instrument systems do have a temperature-controlled column compartment, but what do you do when you are using an older instrument that does not have this? Or what if you need to add another column and there is literally no place left to put in the compartment? Restek has the answer with Sidewinder Column Heaters. The design has just been updated with improvements that you’ll want to check out. Catalog number 25732 has a heating jacket that accommodates analytical columns up to 250 mm in length. Catalog number 25733 has a heating jacket designed for shorter columns up to 100 mm.  Both models provide accuracy within 1⁰C and precision (stability) within 0.1⁰C.

I hope you found this post interesting and thank you for reading. 

Recommended additional reading:

1. How Much Retention Time Variation Is Normal? (chromatographyonline.com)
2. Temperature effects in liquid chromatography - PubMed (nih.gov)
3. Influence of pressure and temperature on the physico-chemical properties of mobile phase mixtures commonly used in high-performance liquid chromatography - ScienceDirect