Tag Archives: non-target

Quantification and its accuracy in nontarget screening

Last Tuesday Jon Sobus from EPA presented some of the findings from a recent paper Uncertainty estimation strategies for quantitative non-targeted analysis, where we were also happy to collaborate, on the BP4NTA online meeting. People from BP4NTA meetings have been reaching out with questions on ionization efficiency-based quantification. Some of these are often asked of us and I decided […]

International Mass Spectrometry Conference 2022 in Maastricht, The Neatherlands

Last week Amina, Pilleriin, and I participated in the International Mass Spectrometry conference 2022 in Maastricht, The Netherlands. With more than 1300 participants IMSC was the first big mass spec conference in Europe after covid and a special feeling of enthusiasm was in the air. We kicked off on Monday morning with a session on […]

Nontarget Analysis for Environmental Risk Assessment SETAC Focused Topic Meeting

Recently, I attended my first in-person conference, the Nontarget Analysis for Environmental Risk Assessment SETAC Focused Topic Meeting. It was held in Durham, NC, USA from May 22 -26 2022, and it was a very intense week filled with interesting talks, posters, and meetings with other scientists. It was very nice to put a face […]

International Conference on Non-Targeted Screening. It was finally time to get back to in-person conferences! 

After almost two years of zoom-only meetings, it was my great pleasure to last week get back to meeting fellow scientists in person at Intentional Conference on Non-Targeted Screening, Erding, Germany. The meeting was held in parallel in-person and online. The conference ran over four days with talks covering computational mass spectrometry, instrumental techniques for […]

What is the potential risk of the compounds detected in water samples? Combining concentration and toxicity

How do you know which of the compounds detected in suspect or non-targeted screening is most likely to cause an adverse effect? Which is most toxic? Which is present in the highest concentration? Which is having a concentration close to a toxic endpoint? This is exactly what we are answering in our latest research in […]

Thesis-Thesis-Thesis: From PCB Metabolites Through PFOS to Reactions in Charged Droplets

The last two weeks have been going under the title “thesis-thesis-thesis” in our group. This spring one BSc student and two MSc students from our group have defended their thesis: Sara Khabazbashi, Helen Sepman, and Thomas Ledbetter. Both Sara and Thomas have dug into the analytical standard free quantification for pollutants. Sara specifically focussed on metabolites of […]

Benchmarking of the quantification approaches for the non-targeted screening

Non-targeted screening with liquid chromatography-electrospray high-resolution mass spectrometry (LC/ESI/HRMS) is revealing hundred to thousands of contaminants in the water. We have recently proposed a way to quantify these contaminants based on the estimated LC/ESI/HRMS ionization efficiencies. But how to know how well such tools are performing? Well, we need to compare with classical methods that are […]

NORMAN interlaboratory comparison on semi-quantitative LC/HRMS

The difficulty in quantifying compounds in LC/ESI/HRMS arises from vastly different responsiveness of the compounds. At the same concentration, two compounds may yield very different signals due to the differences in the ionization efficiency of the compounds. The different responsiveness has made semi-quantitative non-targeted screening challenging. Still, research has been increasingly focussing on enabling the semi-quantification […]

Quantification for non-targeted LC/MS screening without standard substances

Recently we have published a paper on advancement in predicting ionization efficiency in ESI and using this for estimating the concentration of pesticides in cereal samples without the need for analytical standards. In this paper, we explored the possibility to use machine learning for fast and accurate prediction of ionization efficiency. Previously we have carefully […]

Open position: post-doc in computational mass spectrometry

After the move to Stockholm University, my group is looking for new members. Currently, we have available a post-doc position. If you enjoy coding, are interested in machine learning and applying these tools to solve problems in mass spectrometry and you hold a PhD or are graduating soon, this is your chance! For more information […]