How to plan for dirty samples for both extraction and analysis

When juggling the responsibilities of working in a sample preparation lab as well as working as an analyst, it is very easy to get caught up in a never-ending cycle of samples. There is no situation “more frustrating” then when you have a bunch of wastewater samples that need to be extracted and analyzed ASAP and there is that one sample that is so much more challenging to extract than the others. After struggling all-day-long, you finally get the batch of rush samples set up to run on your gas chromatography (GC) system overnight only to come in the next morning to find that your mid and closing check standards are low and the data is effectively useless!

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Simplifying Water Extractions with SPE – One Matrix, One Method Extraction

Have you ever thought to yourself I wish there was one way to effectively extract all of our aqueous samples?  For instance, there are several methods available to extract aqueous samples, such as extraction method 3510 liquid-liquid extraction (LLE), method 3520 continuous liquid-liquid extraction (CLLE), and method 3535 solid-phase extraction (SPE).  Wouldn’t it be more convenient to use one extraction method within the lab for most if not all of your aqueous extractions?

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Your Sample Prep is Only as Good as Your Evaporator

“I love doing maintenance.  It’s the best part of my week” – said nobody ever.

Let’s be honest.  We all dread performing maintenance.  Why?

  1.  It’s boring. I’m a chemist and I’d rather spend my time using my instrument than maintaining it.
  2. It seems unnecessary. I’m a fan of what I call “sensory maintenance” – that water looks pretty clean, that pump sounds pretty good.
  3. I don’t always know what I should be doing for preventative maintenance.

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Understanding SPE Retention Mechanisms

As a chemist, I’ve constantly stressed the importance of proper sample preparation.  Whether I’m diluting, digesting, preconcentrating, extracting, or performing a combination of these, sample preparation is the key to making my analysis a success, yet it’s often the most challenging part of my workflow.  Some of my preparation procedures are simply daunting – a series of challenging, time-consuming steps with multiple opportunities for error or cross-contamination.  On top of that is the multitude of parameters that must be selected.  Questions such as “what should the pH be?”, “which solvents should I use?” and “what should my sample volume be?” are a few of the many, many parameters that must be optimized.  When you look at all the opportunities for something to go wrong, sample preparation can seem very overwhelming.  While powerful, sample preparation becomes a lot less complicated when you understand the science behind what you’re trying to accomplish with this step.

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