A recent blog post written by my colleague asked the question do we have to live with Glyphosate? The answer seemed to be yes we do, for now. Although some countries in the EU have either banned its use or are planning to, while others have implemented strict controls, we simply do not know how long these types of chemicals will remain in the food chain or the lasting effects they may have.
Years ago, the analysis of glyphosate was challenging and some may say that it still is today, but at least now there are advanced solutions available.
Analysis by mass spectrometry, in particular high-resolution accurate mass (HRAM) MS, has emerged as an effective technique to screen pesticides, offering high selectivity and sensitivity.
Couple this to high-performing liquid chromatography (HPLC) using reversed-phase columns you can achieve quantification and confirmation of hundreds of target pesticides in a single run.
GC-MS/MS is probably the most widely used approach and offers full scan targeted and non-targeted acquisition and provides the required sensitivity and selectivity in complex matrices for routine pesticide screening and quantification. It enables the detection and identification of unknown compounds.
Both of these techniques are not amenable to the polar and ionic compounds such as glyphosate, its metabolite AMPA, glufosinate and chlorate to name a few. This is where ion chromatography (IC) excels and yes, you can link it to a mass spectrometer to boost sensitivity and resolution. You could say it is the missing piece of the organic, pesticide-free pie.
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Why Ion Chromatography?
IC systems are made entirely of PEEK (polyether ether ketone) meaning a fully metal-free flow path and no risk of corrosion from harsh acid or base mobile phases (eluents). Clever suppressor technology means these eluents are desalted to water, so those harsh eluents do not enter the mass spectrometer.
Conductivity detection enables us to not only check the separation but also monitor the background, ensuring no salts accidentally enter the mass spectrometer. Solvents can be mixed in post conductivity detection to enable ionisation, making IC compatible with all mass spectrometers.
See this whiteboard video for an introduction to IC.
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The added benefit of IC is that there is no need for derivatization, this is a direct technique for these compounds.
Ion chromatography is celebrating its 45th anniversary this year. Happy Birthday, IC! This means 45 years of development, innovation and column resin experience to bring the most tailored solutions. High capacity ion exchange columns can tolerate food matrices, enabling robust methods to analyse at low concentrations in complex samples.
2019 saw the launch of the anionic pesticide workflow explorer. Giving the capability to analyse 14 anionic pesticides and their metabolites at levels able to comply with regulations and validated in a number of challenging matrices such as wheat flour, baby food and grapes. This provides a total solution for the routine testing laboratory. Learn more in this brochure.
If your lab has challenges with pesticide residue testing, we are here to help, contact us to speak with an expert.
Helpful links to more on pesticide residue testing and IC-MS.