Archive for the ‘Pesticides’ Category

Tips on the analysis of pesticides and mycotoxins in cannabis products: Matrix matters! (Part I)

The growing variety of cannabis products that are currently available in the market speaks volumes about the creativity of entrepreneurs within the industry. Vapes, lotions, balms, cookies, hard candy, gummies, infused drinks, chocolate, fudge, soaps, and tinctures are only a handful of the product types that are currently being commercialized in this ever-growing market. Such […]

Analyzing avocado: How to deal with lack of water and keep the fats out

Avocados are a popular produce item. In fact, the consumption of avocados rose by 450% since 2000! Avocado may be delicious, but it is difficult to deal with in the lab. The good news – avocados are ranked number 1 on the clean 15 list, meaning they have the least amount of pesticide residues. With […]

GC Inlet Liner Selection, Part III: Inertness

The inlet liner is the first surface analytes will interact with after introduction into a GC.  It is critical that liners are deactivated, as a number of adverse interactions can occur between analytes and the glass surface.  Deactivations typically involve some type of silanization of the surface to cover active sites inherent in glass, such […]

Analyzing orange: peel and pulp separately or as whole?

Up to this point, I’ve focused on the optimization of QuEChERS salts and dSPE cleanup with fairly homogenous matrices. So, what about oranges? Should I peel them and analyze only the pulp? After all, that is the edible part. The peel is used as well – pressed into essential oils or scraped into zest. Besides, […]

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 […]

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” […]

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) […]

Pesticides are like Siblings – some get along well and some don’t – No. . .Really?

My colleague, Joe Konschnik and I have been asked by many food chemists out there about how much they can trust their pesticides mixes after they combine them into one single larger mixture for calibrating their instrument, or monitoring the accuracy and precision of their method – and rightfully so.  Well, like siblings, sometimes they […]

What dSPE works with spinach in GC-MS/MS analysis? #NationalSpinachDay

Today is a National Spinach Day! What is a better way to celebrate than to talk about spinach analysis? During part 1 of my blog series, I discussed what dSPE was best for celery. I found that most dSPE, with the exception of dSPE containing high amounts of graphitized carbon black (GBC), showed acceptable analyte recovery […]