How to choose the best elution solvent for SLE?
September 24, 2021 at 2:18 PM / by Stephanie J. Marin, Ph.D. posted in SLE Supported Liquid Extraction, Sample preparation, extraction, solvent polarity, elution
How do I pretreat my samples for Supported Liquid Extraction
July 14, 2021 at 6:09 PM / by Stephanie J. Marin, Ph.D. posted in SLE Supported Liquid Extraction, Sample preparation, extraction, pretreatment
Correct pretreatment of samples prior to supported liquid extraction (SLE) produces better partitioning and cleaner extracts. Supported liquid extraction (SLE) is a simple clean-up technique similar to liquid-liquid extraction (LLE), but on a solid supported surface.
Why should I underload SLE+ plate or cartridge?
July 7, 2021 at 7:00 PM / by Stephanie J. Marin, Ph.D. posted in SLE Supported Liquid Extraction, Sample preparation, extraction
Underloading your SLE+ samples can result in better partitioning and cleaner samples. Supported liquid extraction (SLE) is a simple clean-up technique similar to liquid-liquid extraction (LLE), but on a solid supported surface.
Why just measure Vitamin D when you can monitor Vitamins A, E and K as well?
November 11, 2020 at 2:58 PM / by Alan Edgington posted in SLE Supported Liquid Extraction, Sample preparation, Vitamins
A new method has been developed for the combined analysis of Vitamin A, Vitamin D, Vitamin E and Vitamin K from serum using LC-MS/MS. The method uses supported liquid extraction (SLE) with a novel sample load which could also potentially be employed for many other highly non-polar analytes that have limited water solubility and are highly protein bound within the body.
Troubleshooting Loss of Signal: Where did my peaks go?
October 25, 2020 at 7:45 AM / by Dan Menasco posted in Troubleshooting and Optimization, Sample preparation
Let’s take a look at one of the more irritating issues in LC/MS method development: signal loss. I’m not talking about signal attenuation, which can be much more convoluted to diagnose; but rather a complete loss of signal – nothing, not even a blip on your TIC. So where do we begin?
Putting it Together: why should I tune my mass spectrometer?
October 25, 2020 at 7:30 AM / by Dan Menasco posted in Chromatography Fundamentals, Sample preparation
What's the process behind tuning our analytes to the mass spectrometer’s optics? And why is that so important?
Dilute & shoot ... yourself in the foot
October 21, 2020 at 8:30 AM / by Simonetta Tumbiolo posted in SLE Supported Liquid Extraction, Sample preparation, Method development, Clinical
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.
How to achieve faster sample prep, cleaner extracts, and instant sensitivity gains
October 15, 2020 at 9:06 AM / by Nigel Tooke posted in Sample preparation, Solid-phase extraction, detection limit, Microelution
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?
The revolution of microelution in solid phase extraction
October 15, 2020 at 9:04 AM / by Nigel Tooke posted in Sample preparation, Solid-phase extraction, detection limit, Microelution
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.
How to meet demands for detection limits with the right sample prep
October 15, 2020 at 9:04 AM / by Nigel Tooke posted in Sample preparation, Solid-phase extraction, detection limit, Microelution