Archive for the ‘Enviro’ Category

Got Fast Columns? Clean Up Your 8081 Samples Using CarboPrep Plus as a Substitute for Florisil

My colleague Linx Waclaski blogged about a tale of two columns that started with the introduction of a pair of stationary phases specifically tuned for the resolution of the 20 legacy pesticides found in US EPA Method 8081(1). The story examined the gains in speed over the years as measured by the last eluting compound […]

Are You Interested in Ultrashort-Chain PFAS Analysis? Be Sure to Screen Your Solvents/Solutions for Contamination

Trifluoroacetic acid (TFA) is the perfluorinated analogue of acetic acid with the shortest possible chain length (C2) among per- and polyfluoroalkyl substances (PFAS). Together with perfluorinated C3 compounds, they are defined as ultrashort-chain PFAS. C2 and C3 PFAS are ubiquitous and very mobile in global aquatic environment including rain, snow, river, and even ocean. TFA, […]

A Tale of Two Columns (CLPesticides and CLPesticides2)—Part IV: Fast 8081 Method Using GC Accelerator Kit

The moment has finally come to see how we can use the GC Accelerator to get the most horsepower for your 8081 analysis.  If you’ve been following this blog series, you will remember that in Part II, I talked about ways to make your runs faster.  I also showed you our previous fast “7 minute” […]

TO-15 + PAMS + TO-11A = China’s HJ759 + PAMS + HJ683 part 2: Deans switching and TO-15/PAMS

In a previous blog (TO-15 + PAMS + TO-11A = China’s HJ759 + PAMS + HJ683) Jason Herrington mentioned a dual column MS/FID setup for China’s combined HJ759 + PAMS + HJ683 method. While this could be done with a simple Y splitter (such as https://www.restek.com/catalog/view/1983), a more elegant solution is to use a microfluidic […]

A Tale of Two Columns (CLPesticides and CLPesticides2)—Part III: Using the GC Accelerator Kit for Dual Column Analyses

In my previous two blogs (Part I and Part II), I mentioned the use of Restek’s GC Accelerator Oven Insert Kit (cat. #23849) for making your methods even faster.  The GC Accelerator kit was originally released with the intent of being used with an Agilent GC-MS system; however, this same kit can also be used […]

A Tale of Two Columns (CLPesticides and CLPesticides2)—Part II: Gaining Speed

In my previous blog post, I gave you a little history of the CLPesticides columns.  You’ll remember that I pointed out the 24 minute run times, which were promoted as being fast at the time.  Fortunately, there are ways to attain faster runs on this column pair for standard 8081 pesticides, due to their awesome […]

A Tale of Two Columns (CLPesticides & CLPesticides2)—Part I: A Little History

Chlorinated pesticides are persistent environmental contaminants commonly analyzed using a variety of GC methods, including US EPA 8081, 608 and 508.  Due to similarities in chemical properties of these pesticides, selectivity must be carefully considered when choosing GC columns.  Historically, columns with phenyl methyl (5% phenyl, 35% phenyl, 50% phenyl columns) and cyanopropyl (1701 column) […]

What are GenX and PFBS? Why are they important in PFAS analysis?

Analysis of PFAS (per- and polyfluorinated alkyl substances) has been a hot topic for envoironmental labs for the last several years. Currently there are two C8 based PFAS compounds (PFOA and PFOS) with a health advisory level of 70 ppt in drinking water announced by the US EPA. In 2018 at the National Leadership Summit, […]

Sorry for the delay. Here is your chromatogram with and without the PFAS Delay Column.

Sometimes I hear this from customers: “I don’t need a delay column. I haven’t had any trouble without it so far.” It might be true. You may not have any issues without the delay column, especially when your samples are, for example, highly PFAS contaminated soil samples because the interference is too small to affect […]

What’s That Smell? Odor Analysis with Raptor Biphenyl

  A wide variety of chemicals are used in the production of consumer goods, and most of them have odors that are released into the atmosphere and/or linger on the final product.   Everyone gets really excited about “new car smell,” but sometimes residual odors on fabric or plastic are off-putting. I noticed that the knock-off […]