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.

A prime objective of bioanalytical sample preparation is to achieve high analyte recovery in low elution volumes, with rapid delivery of clean extracts that support robust high sensitivity analysis to meet goals for detection limits. What's best between conventional solid phase extraction (SPE) and microelution SPE?

Solid phase extraction (SPE) is frequently used for sample clean up, trace enrichment (pre-concentration of the sample), or a combination of both prior to analysis. But can solid phase extraction be an effective tool when bioanalysis demands higher sensitivity and reproducibility with decreasing sample volumes? In theory, SPE can be used for targeted extractions with ultra-high concentrations. As we will see, putting this into practice requires miniaturization of SPE extraction using sorbent beds with optimal formats that minimize elution volume to maximize detection and quantitation power.

Highly sensitive techniques such as LC-MS/MS are enabling analytical laboratories to generate more data on more analytes in more samples, in less time, at a lower cost, and using smaller sample volumes. Achieving this performance involves pushing the limits of detection and quantitation with high levels of sensitivity and reproducibility that are only possible with high quality samples.

Most clinical chemists have developed a blood, serum or plasma assay using a protein crash because it is inexpensive and generally removes proteins that interfere with detection or the analysis in some way. But is this always true?

This is a question that I am often asked by very smart people that just haven’t had time to learn the process. An optimized sample preparation method is critical for an accurate, specific, robust clinical LC-MS/MS assay. A good sample prep method can improve accuracy and precision, provide longer LC column lifetime, and keep your LC-MS/MS system clean.

We’ve all been there. We prepare a batch of samples to analyze, prime our systems, warm up the detector, and within 2-3 injections we receive an error message stating that an integral component has failed for one reason or another. This can be a dreadful experience, especially for a routine production laboratory. 

When trying to develop a new method for the detection of a drug panel, you need to refer to reliable sources to learn all you need to know regarding your analytes. For this post, we’ll go in detail through the search process with analytes like naloxone, buprenorphine, norfentanyl and methadone using urine as our matrix of focus.

The sole purpose for method development is to construct a robust and analytically sound method that will not just pass the barriers of validation, but provide physicians and patients with sound and reliable results. But where to start?

Let's face it, the whole solid phase extraction method development process can be time consuming and expensive. So Dilute-and-Shoot methods end up being the choice in some laboratories. The problem is that these methods are dirty and lead to a lot of other issues. In this blog post, I'll be discussing filtration methods and how those are a superior option to Dilute-and-Shoot.