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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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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The Basics of Solvent Drying

Solvent drying is a key step in many laboratories that are using organic solvents for syntheses and extractions. In the case of hexane extractions during oil and grease measurements, this step is necessary to ensure that the extracts are accurately dried, concentrated and weighed.

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