Some polar ionic pesticides and their associated metabolites are not “amenable” to common multi residue methods, such as QuEChERS. These compounds need alternative extraction conditions for improved recovery and/or alternative separation conditions for improved retention and/or peak shape. Currently the polar pesticides tend to be treated as a series of selective single residue methods adding significant cost to the analysis and therefore, are often excluded from pesticide monitoring programs. At Fera we have coupled the QuPPe generic extraction conditions with determination by suppressed ion chromatography tandem quadrupole mass spectrometry. This presentation will describe our experiences and challenge faced in implementing this method, presenting validation data in a cereals matrix. View the presentation here.
Evaluation of Q Exactive LC-MS for Pesticide Residues in Fruits and Vegetables – Plenary Lecture: Abstract: The Thermo Scientific™ Q Exactive™ LC-MS has been evaluated for detection, identification and quantitation of pesticide residues included in the European Union Monitoring Program. Pesticides were analyzed in four matrices representing wide range of difficulty (tomato, pepper, orange and green tea). Read more and watch the lecture here.
Plagued by false or inaccurate results during pesticide analysis? To get to the bottom of the issue, it’s important to find any weaknesses in your pesticide residue workflow. In a recent blog on Analyte Guru, Richard Fussell of Thermo Scientific discusses areas in which pesticide testing labs can identify the weak links, including:
- Solvent extraction. QuEChERs (Quick, Easy, Cheap, Effective, Rugged and Safe) acetonitrile extraction method
- Sample processing
- Extraction efficiency
Get the details about how to find the weakest link in Fussell’s blog here.
More on pesticide analysis:
- New technology a step forward for pesticide analysis
- Need a faster sample prep method for pesticide residue analysis? Try accelerated solvent extraction
In a Q&A with Food Safety Tech, Aaron Kettle, sample preparation product manager at Thermo Fisher Scientific discusses the advantages of using accelerated solvent extraction for pesticide residue analysis and its applications in the food industry.
Food Safety Tech: What are the benefits of using accelerated solvent extraction versus other more time-consuming sample prep methods?
Aaron Kettle: It can save a considerable amount of time over techniques such as Soxhlet and sonication that are used in this industry. In addition, the amount of solvent you’re using is cut down by at least five fold using this technique. The other advantage over some of the other techniques is that it allows walk-away capability, so your samples can be loaded and you can run your methods overnight. It’s pretty much just load the buttons and walk away, and by the time you come in the next day, everything is ready for analysis.
FST: Discuss this method in the context of today’s environment as it relates to importance of detecting the presence of pesticide residue and harmful pollutants.
Kettle: It’s certainly beneficial. It doesn’t have matrix limitations so you can use it for a lot of different sample types: High-fat content samples, such as avocados, dry samples like bread and grain, and high-water content samples like tomatoes.
FST: Are there specific food applications that benefit from accelerated solvent extraction, including those in which the method is underutilized?
Kettle: I don’t think the technique has a lot of use right now for high-water content samples, such as pesticide residue extraction for tomatoes, berries, etc. That primarily has to do with the fact that historically it hasn’t worked well with these kinds of samples. However, we’ve recently released a moisture-absorbing polymer that acts to remove residual water without interfering with the extraction and recovery of the analytes. That has allowed the accelerated solvent extraction to work with these sample types. That’s an area where’s it’s being underutilized right now, primarily because it is a relatively new product release for us. It’s an area where we’d like to see adoption continue to increase.
FST: What is unique about the polymer being used in this detection method?
Kettle: It’s a proprietary mixture that will remove water content up to 85%. There are no major specifics; it will work with any kind of matrix that has water in it—fruits, berries, etc.
FST: What are the top advantages of the technology?
Kettle: The ability to remove residual water is important. It happens prior to the sample being loaded in the extraction cell. There is no limitation with high-water content samples. It mixes well with the dispersing agent, so not only can you add a dispersing agent to help solvent flow through the matrix better, you can also add the polymer to help it through water. It helps expand the capability of the accelerated solvent extraction in what it can do in the food market for pesticide extraction.
FST: What are your expections of this technology within this niche moving forward?
Kettle: We would like to see it expand and have greater awareness and acceptance for the accelerated solvent extraction in this particular area. Right now, folks are using a manual technique for these types of samples, so we’re hoping these customers will accept the walk-away automation and the flexibility that this technique will provide.