Urine samples are composed of many interferents which can cause ion-suppression or ion-enhancement when analyzing by mass spec. Build up of these matrix components over multiple sample injections can lead to loss of signal in the mass spec and even unexpected changes in your chromatographic separation. We are going to discuss why not performing adequate sample prep can be detrimental for your analyses.
When would I choose SLE? When would I choose SPE? We all have faced those questions. Let's have a look at the two sample preparation techniques.
Synthetic cannabinoids are some of the most widely abused drugs in the world. They are structurally similar and have similar effects to marijuana but are frequently referred to as “legal highs”. Chemists are constantly changing the structures of these compounds to keep them in a legal state and governments can’t keep up with adding them to scheduled lists. So, how do we analyze for these compounds? How can they be easily extracted from whole blood?
Have you ever encountered problems loading your samples onto an SPE or SLE plate? Aside from sample viscosity or cartridge blockages, a good troubleshooting step to start with is ensuring that you are achieving complete frit coverage on the load.
Often the question arises asking how can I extract both acids and bases with the same Supported Liquid Extraction (SLE) procedure. Is this possible? And how?
It happens to all of us. We're getting a new method developed and validated and then it comes time to run our negative urines. And everything comes up as positive! There are peaks for our analytes of interest in every urine that we run! How is that possible?