If you are tired of shaking liquid-liquid extractions (LLE) and want to move onto a technique that is less labor-intensive, solid phase extraction (SPE) may be your answer! There are manual as well as automated options available for solid phase extraction. It may seem like more work for your lab to move to a different technique, but what you gain in time savings may be worth it to you in the end.
When in the lab I always try to streamline and improve workflows. One of the biggest bottlenecks in the lab I’ve experienced and maybe you have too, is the drying of sample extracts. When extracting environmental samples, they likely have residual water. Removing water from environmental samples ensures you will get the most accurate and consistent results with both analytical and gravimetric methods. The drying of extracts can be either defined by the method or may have flexibility allowing you to use what is available as long as all quality control criteria are satisfied.
Per- and polyfluoroalkyl substances (PFAS) are a group of harmful organic compounds that are very persistent in structure. What this means is PFAS compounds accumulate in the environment over time as they do not break down easily. This makes it a concern to regulate and test these compounds as they have been shown to have adverse effects. One of the most common ways that someone would come in contact with PFAS is through drinking water. There are two notable EPA regulated methods that laboratories can use to analyze PFAS compounds, EPA method 533 and 537.1. When evaluating how to handle these methods in your lab there are some key differences in how to approach PFAS testing. See our earlier blog extracting perfluorinated compounds from drinking water – why is it so challenging?
Have you ever had days of extracting oil and grease samples and thought to yourself “there must be an easier way to work with wastewater samples”? Whether you run oil and grease samples by liquid-liquid extraction (LLE) or by solid-phase extraction (SPE) it can be challenging at times to efficiently extract 1-liter samples due to the sample matrix. Wastewater is challenging and can be very complicated and contain many types of particulates and or detergents. The makeup of the sample not only interferes with efficient extractions due to matrix issues (such as emulsions) but can also cause slow flow rates.
Have you ever thought to yourself I wish there was one way to effectively extract all of our aqueous samples? For instance, there are several methods available to extract aqueous samples, such as extraction method 3510 liquid-liquid extraction (LLE), method 3520 continuous liquid-liquid extraction (CLLE), and method 3535 solid-phase extraction (SPE). Wouldn’t it be more convenient to use one extraction method within the lab for most if not all of your aqueous extractions?
Working in an environmental lab requires a lot of concentration, both mentally and for the samples that you are working with. When New England finally begins to thaw and local companies rush to get their samples completed, a bottleneck that is usually experienced is the drying and concentration of so many samples. This bottleneck is partly due to ensuring that samples are extracted within their holding times. There have been many times I have had to multitask while concentrating samples on the TurboVap® classic, leading to some extra work when that rare sample was overconcentrated. Many of my past coworkers brought up the challenge they faced with the extraction of water and soils. In my opinion, the bigger issue was drying and concentrating. My main complaint with these steps was it was never efficient enough and I always had to baby each step so that all of my hard work (shaking the sample) did not go to waste. What I strived for most in the lab was an efficient and streamlined workflow for this part of the process.
When preparing your extracts for analysis, it is important to know which instrument to use and why you should be using that specific one. Of course, we know that each EPA method dictates which analysis instrument must be used within each method, however, we will be determining why that option was chosen in the first place in this blog post! Continue reading How does your sample prep change for LC/MS vs GC/MS
Have you ever thought to yourself am I using the best solid phase extraction disk offering for my application? Or can our prep lab turn samples around more efficiently if we choose a different SPE disk platform such as a single-use disk holder instead of cleaning our reusable holders? Those are just a few questions I receive when working with sample prep solutions with customers when SPE disks are brought up in the conversion.
Anyone familiar with Extractable Petroleum Hydrocarbons (EPH) methods such as those developed by Massachusetts DEP, New Jersey DEP, or one of the other various state agencies that regulate EPHs is familiar with the long and grueling process of fractionation. These methods require you to split the initial sample extract into two distinct fractions, the aromatic and aliphatic portions, which allow you to better characterize hydrocarbons that may be affecting the environment (for more info read out previous blog post). It is most commonly achieved through a manual method which is driven by only gravity that can cause quite a bottleneck in the lab. This process can be particularly finicky requiring you to determine the exact volumes needed so that you do not elute one fraction’s compounds into the wrong fraction by mistake. On top of this, the traditional procedure involves the use of gravity to elute the fractions through a cartridge which requires a lot of hands-on time to ensure that the cartridge does not go dry and that it is moved at the correct time. All in all, this process can cause many a headache when it does not run smoothly.
IR technology is a rapid and convenient tool for both qualitative and quantitative analysis that has been around for over a century. Traditional IR spectroscopy relies on vibration energies from the molecular bindings, where IR emission is absorbed by the bond when it has the same frequency as the specific vibration or movement as the bond.