Author Archives: Anneli Kruve

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 […]

Can we quantify chemicals if we do not know their structure? Yes, we can!

Non-target analysis with LC/ESI/HRMS is increasingly used to detect thousands of chemicals in environmental samples. However, most of these chemicals are never confidently identified nor quantified. This in turn means that they are ignored in risk assessments. In our recent paper, we address this issue by modeling the response factor for chemicals without the need […]

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 […]

Cyclic-IMS/HRMS installed in MassSLab at Stockholm University

In September a state-of-the-art cyclic-ion mobility high-resolution mass spectrometer (cyclic-IMS) will be installed in the MMK/ACES joint Mass Spectrometry Laboratory (“MassSLab”). This is the first cyclic-IMS in Sweden and one of the few in Europe. It is envisioned that this new instrument will open up exciting opportunities for novel experimentation while fostering new collaborations both […]