The PhD thesis by Max titled “Advances in thedevelopment of a point-of-care mass spectrometer test“. In this work, an on-site testing method was developed and evaluated for medical examination. For example, this method enabled to determine the concentration of an antibiotic and an opioid directly in blood, plasma, or urine in as little as 5 minutes. Furthermore, traditional laboratory-based methods were developed. These included the diagnose of the rare MNGIE-disease and a 36-second test for the analysis of ecstasy tablets. To investigate potentially harmful drugs added to ecstasy tablets, a large panel of over 100 drugs was measured within a single analysis run on a miniaturised mass spectrometer.
Congratulations to you both! We wish you all the best for the future!
Jaanus Liigand was awarded the 1st prize in category of natural sciences and technology in the Estonian National Contest for University Students supported by Estonian Research Council for his doctoral thesis.
He defended his PhD thesis on “Standard substance-free quantification for LC/ESI/MS analysis based on the predicted ionization efficiencies”. During his PhD studies, Jaanus has worked hard on understanding the mechanism of electrospray ionization in LC/ESI/MS; primarily understanding how the structure of the compound and the eluent used in the analysis influence the ionization efficiency. Jaanus has verified, based on the largest set of ionization efficiencies measured so far (roughly 400 compounds), that the more hydrophobic compounds and more basic compounds tend to have a higher response in ESI positive mode. From the mobile phase point of view, both organic solvent content, pH of the buffer, and buffer composition, influence the ionization efficiency in ESI/MS. In general, higher organic solvent content and lower pH result in higher ionization efficiency and, therefore, a higher response in positive mode ESI/MS.
Dr. Piia Liigand and Dr. Jaanus Liigand
Also, he investigated how well are the ionization efficiency values measured on one instrument transferable to other instruments and found that with the aid of 5-6 common compounds the ionization efficiency values can be transferred from one instrument to another. Combining these promising results and machine learning approaches Jaanus has been able to develop a truly universal approach for applying ionization efficiency predictions for quantification in suspect and non-targeted LC/ESI/HRMS analysis.
He is continuing his research at University of Alberta in Canada in Prof. David Wishart research group to further improve mass spectrometric analysis with machine learning.
Congratulations to you, Jaanus, for the well-deserved acknowledgment!
In the last week of August, the 17thNordic Mass Spectrometry conference was held in Espoo, Finland. With around 150 participants from Nordic countries, the conference covered various different topics within the field of mass spectrometry.
Anneli making her presentation at the 17th NordicMS
From our group, Anneli Kruve presented some of the most recent results in the field of quantitative suspect screening for pesticides and mycotoxins. Riin Rebane presented a poster about analyzing metanephrine (MN) and normetanephrine (NMN) and also about unusual matrix interferences related to the analysis (results have been published here). Artur Gornischeff presented some very exciting results on the ionization studies of derivatized amino acids which have also been published here.
Riin with her poster
Artur with his poster
NordicMS is a mass spectrometry conference taking place every three
years and hosted in turns by nordic countries. This time it was Finland’s turn.
The three-day conference had roughly 150 attendees; as expected, primarily from
Finland and other Nordic countries. The conference covered all major areas of
application of mass spectrometry: food characterization, metabolomics, drug
discovery, proteomics, doping discovery and forensics. Topics covered analysis
from the sea bottom (Hanna Niemikoski’s presentation about the identification
of novel chemical warfare agents) up to the sky (Kari Hartonen’s presentation
about sampling from air with drones).
The conference showed that even in the small circle of Nordic
countries the research in the field of mass spectrometry is diverse and every
mass spectrometry enthusiast will find his or her spot in the field.
In August, additionally two of our PhD students, Piia Liigand and Jaanus Liigand, successfully defended their PhD theses. Both Piia and Jaanus worked intensively and successfully on understanding the ionization process in electrospray ionization source (ESI) and applying this knowledge for quantifying compounds with LC/ESI/MS without standard substances. Congratulations to the fresh doctors! Piia is continuing as a lab manager in TBD-Biodiscovery and Jaanus continues his scientific career at the University of Alberta in Prof. Wishart group.
On 15th of August, Piia Liigand defended her PhD thesis on “Expanding and improving methodology and applications of ionization efficiency measurements”. The opponent of Piia was Prof. Dr. Susan D. Richardson from the University of South Carolina. Over the last four years, Piia has contributed significantly into the development of ionization efficiency measurement methodology. She has been able to develop a method for measuring the ionization efficiencies for both small molecules as well as oligopeptides. Most of all, she has shown that the predicted ionization efficiencies can be applied for drug and drug-a-like measurements in the biological matrices. And, last but not least, she has pulled together a large number of response factors from the literature and shown that these values are in good agreement with each other in spite the, sometimes observed, contradicting conclusions.
Piia with her supervisors Dr. Karl Kaupmees and Prof. Anneli Kruve and opponent Prof. Susan Richardson
Jaanus Liigand defended his PhD thesis on “Standard substance-free quantification for LC/ESI/MS analysis based on the predicted ionization efficiencies”. Prof. Dr. Jonathan Martin acted as an opponent of the defense. During his PhD studies, Jaanus has worked hard on understanding the mechanism of electrospray ionization in LC/ESI/MS; primarily understanding how the structure of the compound and the eluent used in the analysis influence the ionization efficiency. Jaanus has verified, based on the largest set of ionization efficiencies measured so far (roughly 400 compounds), that the more hydrophobic compounds and more basic compounds tend to have a higher response in ESI positive mode. From the mobile phase point of view, both organic solvent content, pH of the buffer, and buffer composition, influence the ionization efficiency in ESI/MS. In general, higher organic solvent content and lower pH result in higher ionization efficiency and, therefore, a higher response in positive mode ESI/MS. Also, he investigated how well are the ionization efficiency values measured on one instrument transferable to other instruments and found that with the aid of 5-6 common compounds the ionization efficiency values can be transferred from one instrument to another. Combining these promising results and machine learning approaches Jaanus has been able to develop a truly universal approach for applying ionization efficiency predictions for quantification in suspect and non-targeted LC/ESI/HRMS analysis.
From 1st to 6th of June, two PhD fellows Piia Liigand and I presented our recent results at 67th ASMS annual conference in Atlanta, USA.
100% renewable energy utopia or reality?
The conference was kicked off with a plenary lecture by Prof. Mark Z. Jacobson on the topic of “Transitioning the World Energy for All Purposes to Stable Electricity Powered by 100% Wind, Water, and Sunlight”. He introduced how global, country wise, neighbourhood and individual energy production and preservation are feasible based on 100% renewable energy. I found fascinating the example of Prof. Jacobson himself as he has built his own house that uses and produces 100% renewable energy needed for maintaining the house and charging his electric car.
From simple ambient ionization techniques to “fishoil” from canola
The conference consisted of four days full of exciting talks which covered the fundamentals of mass spectrometry to application in diverse fields from cannabis analysis to proteomics. It was very encouraging to hear about the journey of Prof Dr Sarah Trimpin, this year Biemann medal awardee and her studies of very simple ionization techniques. I found exciting the results of a group from CSIRO, Australia. They applied mass spectrometry in food safety analysis, but even more fascinating was the genetically modified canola which can produce omega-3 fatty acids in large amounts to prevent overfishing to obtain omega-3-rich fish oil.
Quantem provides unification of ionization efficiencies from literature and standard substance free quantification in LC/ESI/MS
The conference ended with the gala dinner in Georgia aquarium. The sea life, especially whale sharks and beluga whales, were astonishing. It was great to meet old friends and get to know new ones. We thank the ASMS team for a very nice conference in Atlanta and hope to meet next year in Houston at 68th ASMS annual conference. Additionally, we thank Graduate School of Functional materials and technologies and Kristjan Jaak scholarship for travel costs.
Built on the foundation of several years of research on ionization efficiency by Kruve et al. there is now an easy-to-use tool to quantify analytes in LC/ESI/MS analysis without the use of standard substances.
The availability of standard substances is one of the main limitations in LC/ESI/MS analysis, especially in the fields of metabolomics, environmental analysis as well as illegal substance monitoring. If no commercial standards are available, the only choices so far have been to either (1) synthesise these in-house which is very expensive and time-consuming or (2) use other compounds for quantification and ignore the possibility of vastly different response factors. The latter choice could lead to errors up to 10 million times. Now, a third, overwhelmingly faster, cost-effective and accurate option has been developed.
A team consisting of scientist associated with Chair of Analytical Chemistry has launched their company Quantem Analytics aimed at providing standard-substance-free quantification solutions for LC/ESI/MS analysis. They combine the fundamental research[1][2][3] in the field of mass spectrometry with data science to provide the first solution to situations where there simply are no standard substances available for quantification. Quantem uses machine learning to predict response factors of analytes taking into account the eluent composition at the retention time. Their novel approach is applicable to:
Numerous types of analytes with logP from -10 to +10 and molar mass below 1500 Daltons;
Different matrices, e.g. urine, plasma, liver, and cereal;
All common eluent compositions, both in terms of organic modifiers and additives;
Both positive and negative mode ESI;
Gradient elution, including different flow rates;
This, in turn, opens various new possibilities:
Switching to an approach where your quantification is not limited by the availability of standard substances but rather your ability to identify the peaks;
Quantification of more than 1000 peaks within 24 h;
Retrospective analysis. Quantification of analysis data acquired even years ago;
Direct comparison between standard-substance-free analysis results obtained on different instruments and even in different labs opening the door for large scale collaboration in the field of quantitative non-target analysis;
The accuracy of the Quantem predictions is high, the average error is below 5 times, i.e. if the method predicts a concentration of 1 ppm the true values is probably in the range of 0.2 – 5 ppm. In the vast majority of cases, this is sufficient input for making data-driven decisions.
If you have any further questions you can contact Quantem through https://quantem.co
The measured ionization efficiencies in different solvent systems. The colour of the box plot background shows the organic modifier (90%): Green – Methanol, blue – Acetonitrile, red – Acetone, orange – Isopropanol. The letter shows the water phase additive (10 mM): F – Formic acid, O – Oxalic acid, P – Propionic acid
Recently a study in Rapid Communications in Mass Spectrometry was published. In this study, we optimized the actual split ratio and make-up flow composition in LC/ESI/MS analysis to increase the signal in radio detector and enhance the sensitivity of electrospray ionization.
High methanol content increases electrospray ionization efficiency
We studied make-up flow composition with a set of 20 pharmaceuticals covering 21 different make-up flow compositions. We studied methanol, acetonitrile, isopropanol and acetone as organic modifiers. As we studied positive mode the acidic additives under investigation were formic acid, oxalic acid and propionic acid. DMSO and sulfolane as additives were studied as well. The Methanol/10 mM formic acid in water (90/10) proved to be the best make‐up flow composition in relation to the average sensitivity obtained. Stronger acidic conditions using oxalic acid or higher formic acid concentrations had a clear positive effect on the sensitivity of compounds with low ionization efficiency.
Split-ratios remain stable over main part of the gradient
The second part of this study was testing and monitoring different split ratios (1:10, 1:100 and 1:250) with different splitters (Alliance flow‐splitter kit and homemade T-piece splitter). To monitor the actual split ratio haloperidol solution was added with infusion pump post-column while a haloperidol-d4 solution was added as a make‐up flow by the ISM pump after the splitter. The tested split ratios were relatively stable over the main part of the gradient but showed some variation at very low and very high organic conditions. Differences were larger with methanol compared with acetonitrile containing solvent compositions and when applied without a column or with very long connecting tubing.
I thank Janssen Pharmaceutica and especially Dr Filip Cuyckens for the internship position for letting to gain experience in an industry setting and study these effects. Additionally, I thank Erasmus+ mobility and Smart specialization doctoral stipend for funding my stay.
Dr. Anneli Kruve defended her PhD thesis – “Matrix effects in liquid-chromatography electrospray mass-spectrometry” in University of Tartu in 2011 under the supervision of prof. Ivo Leito and dr. Koit Herodes. Right after she got her first personal funding and established the electrospray ionization efficiency studies group. In addition to understanding the ionization mechanism for small molecules in electrospray, she is interested in using charged nanodroplets generated by electrospray as an organic synthesis medium. In 2016 Dr. Anneli Kruve moved to Haifa, Israel to do her first post-doc at the Technion’s Schulich Faculty of Chemistry in Prof. Israel Schechter’s group. Right now, she is a Humboldt Fellow in the Institute of Chemistry and Biochemistry at Freie Universität Berlin in Germany in Prof. Christoph Schalley’s group.
In addition to excellent science, she is spreading the knowledge as she has designed and is actively lecturing different courses (instrumental analysis lab, statistics in analytical chemistry to name some) in analytical chemistry and statistics in analytical chemistry. She has also supervised several PhD and numerous MSc and BSc students.
Early inspiration
“I got started in organic synthesis but quickly joined a biomedical lab that needed students to operate a HPLC. From there, moving to LC/MS was a natural step. The ability to incorporate various skills from IT to synthesis with mass spectrometry-based research has kept me motivated to stay on this path.”
Research
“My field is structural and quantitative characterization of compounds with LC/ESI/IMS/MS. A key focus of mine is developing the possibility of giving a quantitative context to non-target LC/HRMS data without the need for standard substances.”
Greatest achievement
“I have already seen many students moving from our lab to the workforce and receiving positive feedback from their employers – that definitely makes a former supervisor happy!”
Prediction
“Mass spectrometry has already changed almost everything; its impact will increase further, as we make non-target screening more efficient with effective algorithms, and make it quantitative. I also have a dream technique: I sometimes wonder what the world would look like with MS-(gas phase)NMR . . .” (The Analytical Scientist)
We are very happy and proud that Dr. Anneli Kruve received this well-deservedly recognition of being nominated to the Top 40 Under 40 Power List by the Analytical Scientist!
From the 9th to the 13th of September MSACL EU 2018 Annual Congress took place in the cosy city of Salzburg, Austria. This conference was designed to mass spectrometry audience mainly focusing on clinical applications. I had the opportunity to participate in this inspiring conference. Moreover, I had the possibility to give a talk. I introduced our studies on standard substance free quantitation in LC/ESI/MS analysis.
Lightning talks to encourage young scientists
Prof. Jerzy Adamski kicked off the conference with the plenary lecture on the topic “Metabolomics Messages on Human Health and Diseases”. As one of the main goals of this conference is to inspire and encourage the young scientists the next session was lightning talks. Poster presenters had 90 seconds and one slide to present their research and cultivate interest in their topic. Additional possibility to get to know mature scientist was the program “meet the experts”. There were short meetings as well as booth and poster tours with experts. I had the possibility to analyze some posters together with Dr. Oleg Mayboroda from Leiden University Medical Centre. It was nice to see how the experts look at the posters and how and which questions they ask. Dr. Mayboroda gave a checklist of how to assess the goodness of the PCA plot presented on posters.
Scientific highlights of the conference
There were 5 parallel sessions every day. For me, the three highlights were as follows. First of all, Dr. Mario Thevis gave a talk about mass spectrometry in sports drug testing. Also, Prof. David Millington gave an interesting talk about the role of tandem mass spectrometry in newborn screening. It was encouraging to see how the methods developed by his team save around 2500 newborns on yearly basis. Furthermore, Dr. Lyudmilla Yanshole gave a talk about using postmortem tissues for biomarker identification. It is an interesting study as for lots of diseases it is very difficult to get tissue of healthy species.
Standard substance free quantification LC/ESI/MS
I had the possibility to present for the first time a talk at an international conference. For that, I am most grateful for the MSACL organization and the scientific committee. I introduced the recent results on the feasibility of standard substance free (semi)quantitation in LC/ESI/MS using ionization efficiency prediction models. We have measured more than 2000 ionization efficiency values. We have incorporated 21 solvent compositions. The models are developed based on descriptors calculated from the 2D structure of compounds and the predictions perform well even in complex matrices, namely, bodily fluids. Our average misprediction of ionization efficiencies is less than 3.5 times mismatch. I thank the audience for fruitful discussions on the topic.
Salzburg is a lovely city with stunning views of the Alps. Furthermore, the organizer made our stay at the conference very enjoyable with the nice coffee breaks and warm buffet for lunch and dinner which were offered every day.
From 26 to 31 of August Florence hosted a vast majority of mass spectrometry scientist in the course of 22nd International Mass Spectrometry Conference. Among these were also our group members researchers Anneli Kruve and Riin Rebane, PhD students Piia Liigand and Jaanus Liigand, MSc student Mari Ojakivi and a visiting PhD student Tingting Wang from the Technical University of Denmark. We had a chance to present altogether 5 posters at the conference. Our posters can be found here. As is the case for IMSC, the topics ranged as wide as it can be for mass spec and always there was something to see and hear. We were happy to see that there was a lot of interest in our work. Congratulations to Anneli, whose poster received Chemistry – A European journal poster award! The conference was accompanied by delicious Italian food and nice warm weather. We enjoyed every second of this highly intensive week and are looking forward to IMSC 2020 in Rio.
Anneli Kruve: It is no secret that I am very keen on non-target screening methods, so I really enjoyed all the talks and posters regarding non-target screening and compound identification. My favorite talk was actually also in the field of compound identification given by Prof. Rober Mistrik in the Thermo lunch seminar. He very nicely explained the Precursor Ion Fingerprinting strategy and explained some of the new tips and tricks which are now combined in the Mass Frontier 8.0. It also very strongly resonated with the perspective I recently wrote about semi-quantitative non-target screening. I also have to mention the plenary lecture by Prof. Marco Leona from Metropolitan Museum of Art, who did not focus specifically on mass spec but gave us a really nice overview of scientific research of art. I constantly kept thinking how beautiful it is to have a background in chemistry: one can, virtually, combine all interest and make a great new whole. Prof. Leona, for example, was combining beautiful artworks, history of humankind, the biology of colorful bugs and plants, and on top of that mass spectrometry. And I definitely also felt honored to receive my best poster prize awarded by Chemistry – A European Journal!
Riin Rebane: It was my first experience of Florence as well as IMSC and when the first one greeted with wonderful food, the second one gave food for thought. It was a thorough overview of the latest advances in mass spectrometry and an insight into different works of scientists from academia as well as industry, therefore, it was certainly a challenge to grasp it all. But despite that, it was also nice to see that sessions towards practical applications of mass spectrometry in for example food or environmental analysis, were so popular that arriving late meant that all seats were already taken by other enthusiasts.
Mari Ojakivi: IMSC 2018 was the first scientific conference that I attended and as a master’s student it was an eye-opening experience. It was very nice to see so many scientists introducing their brilliant work with a mass spec. Seeing all the different applications in forensics, food and environmental science, as well as fundamental research in all the -omics fields made me understand how powerful tool mass spectrometry is. What is more, presenting my own work and seeing other scientists being so interested in it, verified that I am doing good and important science.
Piia Liigand: I thoroughly enjoyed the IMSC 2018 in Florence. It was a nice opportunity to meet and talk to scientists from all over the world. I was also very positively surprised to see so much interest in my poster and I truly enjoyed the discussions I had while presenting my poster. Thanks to these discussions I now have even more understanding of the importance of the science we do and what to do next. I also enjoyed meeting friends from past conferences and catching up on their research in more detail. Of course, the food, wine and general ambiance of Florence was an excellent environment to do all that.
Jaanus Liigand: I enjoyed the IMSC 2018 in Florence as it offered a very wide set of different interesting topics of mass spectrometry field. The inspiring presentations, fruitful discussions, interdisciplinary ideas, and excellent community made it a very enjoyable conference. My favorite session was environmental MS where Prof. Susan Richardson gave in her keynote a very nice overview of the recent developments in this field followed by interesting presentations. Additionally, I enjoyed meeting friends from previous conferences and discussing their and our research. Of course, the historical city – Florence – with the food and wine scenery made the week even more enjoyable.
Tingting Wang: It was a really memorable experience to participate IMSC in Florence, and I enjoyed the atmosphere and all the academic events there. It’s so impressive how wide are the application fields that mass spectrometry can do in the world by looking through a thousand posters. It’s hard to say which presentation or poster was my favorite, but I do pay more attention to the non-target screening strategy applied in food control, environmental, metabolomics, and proteomics study, especially the workshop on the second day about non-target analysis. It was interesting and very informative because unknown screening by high-resolution mass spectrometry is the topic of my PhD project, how to combine target and non-target screening, how to develop a more precise identification and quantification strategy for the non-target even unknowns, and how to prioritize unknowns are the problems I am always facing. It is nice that I could see these similar studies with various workflows from other researchers, and have the chance to listen to their presentations and even talk with those people to get inspiration for my research.
Anneli, Riin, Mari, Jaanus and Piia presenting their posters.
The dissertation by Ruta was titled “Novel eluent additives for LC-MS based bioanalytical methods”. In this thesis, novel fluoroalcoholic eluent additives that showed to have a positive influence on analyte ionisation in the MS source were studied. Additionally, two practical applications employing novel eluent additives were developed and validated for several pharmaceuticals. The two bioanalytical methods were used to obtain data for pharmacokinetic and pharmacodynamic studies in paediatric patients. Both methods reached exceptionally low limits of quantification, with minimal sample amount used due to the positive influence of novel eluent additives on analyte ionisation.
