Troubleshooting HPLC- Tailing Peaks  

As in the previous posts for this series, these suggestions assume that you are working with an established method and had successful results in the past. If a method is rugged, it is developed to minimize tailing by using a stationary column phase that is base-deactivated as well as appropriate modifiers and pH adjustment in the mobile phase as needed.  Keep in mind that if the method is not as rugged as it should be, change(s) in the method might be advised if tailing continues to be an ongoing problem.

With troubleshooting, as always, it is critical to note when the change occurred and how it might correlate to changes in the system.  Equally important is to change one thing at a time to identify the source(s) of difficulty. The following are examples of things that could contribute

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Troubleshooting HPLC- Loss in Response for Some, but Not All Analytes  

Patterns in your HPLC chromatography can exhibit telltale signs that point toward probable sources of error.  In this brief series of posts, we will look at possible scenarios that you may encounter in the laboratory and how you might approach resolving those difficulties.
When some, but not all of your peaks are low, and you are analyzing multiple analytes, the number one rule is to look for trends. As mentioned in the previous post for this series, when you have only one analyte, or a handful of very similar analytes, the following may also apply. Again in this post, the assumption is that you are using an established working method and that you see a loss in response for every sample or standard that is injected. If you are only seeing the problem with samples and not your quantitation

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Troubleshooting HPLC- Loss in Response for Some, but Not All Analytes  

Just as in GC applications, patterns in your HPLC chromatography can exhibit telltale signs that point toward probable sources of error.  In this brief series of posts, we will look at possible scenarios that you may encounter in the laboratory and how you might approach resolving those difficulties.
We occasionally get calls or emails from folks that are seeing lower than expected response for peaks of interest. This may be a matter of method development if you have not done this analysis previously. Suggestions in the post are provided assuming you are working with an established method and have had successful results over an extended period of time (until recently). These suggestions also assume that the response is low for quantitation standards as well as in prepared QC samples. If

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Troubleshooting HPLC- Loss in Response for all Analytes  

Just as in GC applications, patterns in your HPLC chromatography can exhibit telltale signs that point toward probable sources of error.  In this brief series of posts, we will look at possible scenarios that you may encounter in the laboratory and how you might approach resolving those difficulties.
We occasionally get calls or emails from folks that are seeing lower than expected response for peaks of interest. This may be a matter of method development if you have not done this analysis previously. Suggestions in the post are provided assuming you are working with an established method and have had successful results over an extended period of time (until recently). These suggestions also assume that the response is low for quantitation standards as well as in prepared QC samples. If t

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