Why does your SPE disk need to be dry?

Every step within a solid phase extraction (SPE) procedure is imperative, but one of the most important steps that must be done properly is the air-dry step.  As you may know, the conditioning step prepares the SPE prior to the sample load to ensure that the sample load process will capture the analytes of interest within the media bed.  However, once the sample is done loading, there is a lot of water that is left on the disk.  Depending on the solvents that you are using following sample load and the analytes you are capturing, an improperly dried SPE disk could ruin your day.

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Common Mistakes by the Lab Series: The Pain of Contaminated Squeeze Bottles

Ugh…I think we can all agree that the worst thing that can happen when testing high profile samples is losing an extract due to phthalate contamination.  Whether you are extracting 525.2 or 625.1 samples, phthalates can ruin your day and wreak great havoc, causing false positives!  We wonder where they all come from and how they got in the extract in the first place because we try our best to make sure our lab supplies and instruments are clean.  As we all know though…phthalates are literally everywhere floating around in the air and settling on surfaces.  However, I am here to talk about one place in particular: solvent squeeze bottles.  We take extra precautions when refilling our squeeze bottles, but there is always the potential of introducing phthalates into them if they are not refilled or used properly.

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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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Why are my phenol recoveries low on my EPA Method 8270/625.1 extractions?

Do you have issues seeing acceptable recovery of your phenols?  I know I do.  These compounds can be challenging to recover and quantitate, and are also found just about everywhere!  Read on to learn a couple of fun facts about phenols, but first, let’s explain why phenols can be difficult to work with.

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Common Mistakes in the Lab

When working in a contract lab or any analytical testing lab, you may be prone to periods where it seems like there is never going to be a light at the end of the tunnel, as the samples just keep on coming in. For me, I always dreaded when spring rolled around and the whole world thawed out because I knew samples would start coming in nonstop since everyone and their mother wanted to get their quarterly testing done. When faced with what seems to be such an insurmountable workload some of your normal good lab practices might take a hit if you are rushing to extract before a sample’s hold time expires. One such good lab practice is properly cleaning the glassware or anything else that might come in contact with your samples.

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Are Your Proficiency Testing Results Failing for EPA Method 1664 with SPE?

It is that time of year again when laboratories are fulfilling accreditation requirements for the methods that they offer. One of the requirements that must be met for each method is called proficiency testing (PT). If you are not familiar with proficiency testing, it is a sample purchased from an approved vendor to evaluate the ability of a lab to meet the acceptance criteria of the method.  If the labs’ results are out of the PT samples acceptance criteria, they can redo the testing.

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Hydrophilic Solution for Your Vapor Lock Dilemma

Have you ever put your water sample onto your Biotage® Horizon 3100 extractor and all your prewet/conditioning steps worked great and then suddenly, the water inlet valve opens, and nothing happens!  This can be terrifying because a lot is riding on those samples!  If you notice this right when it happens, a simple wiggle of the sample bottle should introduce air into the bottle releasing the water, in turn loading your sample.  However, you do not want this happening all the time, especially when you leave your extractor for a while, come back, and see that your sample never loaded!

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To Be or Not to Be Water Miscible

“Oh my!  This is crystal clear!” – said nobody who has ever read through an EPA Method.

For anyone who processes samples in an EPA-regulated laboratory, you know that these methods can be very specific in some spots, and incredibly vague in others.  The complexity worsens if you’re following one method for sample cleanup and another method for sample preparation and data collection.  Consult this handy infographic to make sure you’re following the right methods for sample cleanup, processing and analysis.

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Spooky Stories or Laboratory Mishaps?

“There is a child in every one of us who is still a trick-or-treater looking for a brightly-lit front porch.” – Robert Brault

It’s Halloween!  I assume you’ve carefully assembled your favorite movie character, comic book superhero or animal costume for a night of spooky fun.  If you’re me, this is the day you get to wear your superhero cape out in public.  As an applications chemist, I consider myself to be a bit of a superhero – but a humble one, as I wear my cape underneath my t-shirt and lab coat.  I consider myself to be a superhero when I’m able to use my background and my experiences to think quickly on my feet and help troubleshoot challenges that chemists face all the time.  It’s one of the best parts of my job and I’m thrilled each time I get to wear my cape – metaphorically speaking.

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Are You Contaminating Your Samples During Evaporation?

“Water in my extracts again?!?!”

How many of you have been in that position?  You’ve worked hard to extract your samples, you’ve dried your extracts to remove the last droplets of water from your organic solvent – only to add that water back in during your evaporation step!  There are fewer frustrating situations than losing a set of extracts in this manner.

If you’re like me, you work hard, follow all the precautionary step-by-step procedures to carefully produce extracts in a timely fashion.  It’s frustrating to think that a whole day’s work can be ruined with just a few milliliters of water.  When you see the water, you make an attempt to remove it and save your extracts, but there’s no guarantee that it’ll work.  Is there any way to avoid this?

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