Tech Tip 8: How do you know when a suspected problem really is a problem and not imagined?

Failing to identify a problem early can result in it possibly becoming a major problem with lots of down-time and costs involved in solving and fixing it. Many samples may also need to be re-analysed adding to costs, time, stress and customer satisfaction. Conversely, thinking that there is a problem when there isn't really one can also lead to all of these things with lots of tail-chasing and not really getting anywhere.
 
When first developing a method, collecting together information regarding both the instrument and the method when it is finished and validated into one place can help to identify if there is a problem early on and if it truly is a problem.
 
Gathering instrument information includes:

  • The detector noise level when at the initial method parameters and a print-out of the baseline profile when an instrument blank is run to help identify sensitivity issues, detector problems and column bleed.
  • If the mass spectrometer has a vacuum gauge making a note of the typical vacuum at that column flow helps to identify MS sensitivity problems and larger leaks.
  • Keep air & water and tune reports nearby for comparison. What should the values ideally be? What are the limits?
  • What does the instrument usually sound and smell like? What do the components look like when not broken?

 
Method-related information includes:

  • Print-out of a typical chromatogram of a standard like an AQC or system suitability check standard showing peak separation, peak shape and relative ratios of the analytes.
  • Storing this standard in the freezer means it can be re-run to identify if a problem is the standard, a sample or the instrument.
  • Keep a hard copy of all method conditions - methods have been known to get corrupted, even backup electronic copies!

Collecting this information together in hard-copy format into a file next to the instrument means that it is easily accessible for daily maintenance and checks as well as in the event troubleshooting needs to be performed quickly. A schematic of the instrument set-up for the method can also be useful for troubleshooting purposes to help identify the source of the problem.

To learn more about GC & GC-MS troubleshooting, attend Day 5 of our Complete GC & GC-MS course and Module 12 of our Virtual Classroom Complete GC & GC-MS course.

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