Influence of sample temperature on the chromatogram

[greg07]

Hello forum members,

I would like to ask if there is a known effect of sample temperature on the chromatogram? Let's assume for simplicity that the temperature of the column is 30 degrees C, phase 4:1 (methanol/water) and we inject this mobile phase from the vial at a temperature of 25, 20, 15, 10 degrees C. What results will we get?

[Consumer Products Guy]

I would figure negligible.

[tom jupille]

Depends on the detector. I dimly remember (3.5 decades ago!) seeing a "temperature" peak on an RI detector. The mobile phase was pure water, and the sample (carbohydrates) was dissolved in water as well. The column and mobile phase were at 65 degrees, and we could see a difference in the t0 peak between ambient-temp and 65 degree temp samples. Not enough to cause a problem.

Since UV detectors usually have some sensitivity to RI changes, I expect that you could see the same sort of thing if you looked hard enough, but I agree with CPG that you would have to look *very* hard to see it.