Room temperature influences peak shape. Heat emission data?

<p>Hello,</p><p></p><p>during summer we noticed the influence of the room temperature (as well as humidity) on our LC-MS/MS systems, especially the MS part. Here we could see shifts in the m/z of our analytes which resulted in very low peak heights. Unfortunately we are a university hospital and the results of our methods directly influence the treatment of our patients. As a consequence, we daily had to tune our analytes to correct the masses. I don't have to tell you that this is very time consuming and impractical. We had several Waters technicians to work on this problem but no one 1. ever heard of this problem and 2. could help us. Does anybody has similar problems?</p><p></p><p>We bought a second air conditioning device and somewhat could minimize the problem. However, this device will have to be replaced with a new climate control unit because it consumes to much lab space. Are there any data on the heat emission of the LC-MS/MS systems?</p><p></p><p>Our LC-MS/MS systems:</p><p>- Acquity UPLC - Quattro Premier XE with an Edwards E2M28 vacuum pump</p><p>- Waters Alliance 2795 - Quatro Micro API with an Edwards E2M28 vacuum pump</p><p></p><p></p><p>Thank you very much for your help!</p><p></p><p>Susan</p>


  • RD


    I have encountered similar issues with the Quattro Premier  that were eventually traced to poorly controlled room temperature.  In my case the fix was simply to make sure that the air conditioner was not cycling off during the evening to save power but was programmed to maintain the same consistent temperature throughout the day.

    Unfortunately, the RF generators of these devices are subject to drift caused by ambient temperature changes.  The attached Site Preparation document suggests that the maximum room temperature fluctuations be no more than +/- 2 C.

    Hope this helps.


  • Dear Rich,

    thank you very much for the information. At least I know now that I'm not alone with this problem.