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.
Believe it or not, we’re all familiar with emulsions. Have you ever added food oil to a pot of water while cooking? That’s an emulsion. Do you put dressing on your salad? It should be called salad emulsion – although, that may not have the same edible appeal. Do you drink milk? Emulsion. What about milk? Butter? Eggs? All emulsions.
If we’re referring to emulsions in the laboratory, the examples are different, but the chemistry involved is very similar – as are the mechanisms for breaking them. Continue reading Tackling Emulsions Just Got Easier
Liquid-liquid extraction (LLE), supported liquid extraction (SLE), and solid-phase extraction (SPE) have existed for decades and if you’re doing organic sample preparation, you’re probably quite familiar with at least one of these techniques. But are you familiar with all of them? How are they similar? How are they different? Let’s review! Continue reading SLE, SPE and LLE – How are Those Different?
“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.
Pesticides have been widely used in the U.S. for decades to combat everything from weeds to insects to bacteria. These compounds allow farmers to cultivate acres of successful crops and keep food on our dinner tables. But every chemical poses a risk, so I always like to familiarize myself with the chemicals I’m being exposed to, in order to make informed decisions about the health and safety of me and my family. Here are a few facts about pesticides I thought I’d share – just in case you’re on the same fact-finding journey I am.
If you’re reading this blog and hoping for a sneak peek at the list of contaminants that will be on the next UCMR list, you’ll want to keep reading…
Have you ever stopped to enjoy a bright, vibrant sunset, only to have that really annoying friend interrupt your thoughts with a comment like “you know you’re just looking at all the pollution in the air, right?”
I used to wonder how someone could focus on pollution while looking at a stunning landscape, but it’s becoming a topic that more and more people are thinking about.
“Why do I keep seeing background contamination from phthalate and adipate when I do extractions for semi-volatiles?”
This is one of the most common questions I’ve been asked when I’m traveling in the field. It’s an issue I’ve come across in my own lab on occasion and if you can’t find the source of your contamination, it can turn routine application work into a troubleshooting nightmare. Given how often I’ve seen these compounds cause contamination issues, I thought I’d review some of the most common sources for these. Continue reading 5 Sources of Phthalate and Adipate Contamination You Probably Didn’t Know About