We are happy to introduce: Dr. Piia Liigand and Dr. Jaanus Liigand

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.

Once more – congratulation to you both!

Synthesis and characterization of novel phosphazene-based indicator molecules

On August 22, 2019 Sigrid Selberg successfully defended her PhD thesis titled Synthesis and properties of lipophilic phosphazene-based indicator molecules.

The dissertation presented by Sigrid Selberg is focused on the design and synthesis of a family of highly lipophilic phosphazene based indicators. 16 new phosphazene based indicators where phosphazene structure is extended with an azo group or with 4- (trifluoromethyl)coumarin backbone were synthesized and characterized, indicators are active in both visible absorption and fluorescence. These compounds are highly lipophilic in both neutral and protonated form, therefore, the synthesized compounds have all the desired and suitable properties to employ them in the design of an optical pH sensor. For the first time, alkyl and aryl phosphazenes are used for this purpose.

In addition, the original approach for quantifying acidity/basicity of lipophilic molecules in water-immiscible media that is at equilibrium with aqueous phase is developed and applied in the determination of biphasic pKa values of some of the synthesized compounds.

Congratulations to you, Sigrid!

Our acid-base research at 19th European Symposium on Fluorine Chemistry 2019

On 26.08.19 at 19th European Symposium on Fluorine Chemistry 2019 Ivo Leito gave a talk Acidities of molecules and media: the united pKa-pHabs scale in 1,2-dichloroethane.

For the first time in a low-polarity solvent, the scale has a dual nature, being both a pKa scale of the involved acids (i.e. describing acidity of molecules) and at the same time a pH scale, describing the acidity of the solutions (media).

The scale spans 28 orders of magnitude (pH or pKa units) and is composed of 87 acids of diverse nature. The scale is linked to the unified acidity (pHabs) scale and expressed in values, which makes the acidities of the solutions directly comparable to the conventional aqueous pH scale. This in turn makes the scale a useful tool in future studies of acid-driven processes (reaction mechanisms, catalysis, strong oxidants, etc) in low-polarity media.

This work has been published in: Chem. Sci., 2017, 8, 6964-6973. A unified view to Brønsted acidity scales: do we need solvated protons?.

It is part of a larger endeavor – to promote a wider usage the unified pH scale by the research and technology communities, which is currently in progress via the UnipHied. The project is funded from the EMPIR programme (project 17FUN09) co-financed by the Participating States and from the European Union’s Horizon 2020 research and innovation programme.  

EACH is featured in Analytical and Bioanalytical Chemistry!

The educational section of the leading analytical chemistry journal Analytical and Bioanalytical Chemistry, the ABCs of Education and Professional Development in Analytical Science has published a paper about the EACH programme: EACH (Excellence in Analytical Chemistry), an Erasmus Mundus Joint Programme: progress and success

The EACH programme is an Erasmus Mundus Joint Master Degree programme coordinated by our group. It has become one of the leading master’s degree programmes focusing on analytical chemistry within its short existence. The programme is run in cooperation by four top European universities: in addition to the coordinating university, the University of Tartu (first-year university), also Uppsala University (Sweden), Åbo Akademi University (Finland) and University Claude Bernard Lyon 1 (France) are involved as second-year and specialisation institutions.

The paper gives a comprehensive overview about the EACH programme, including a detailed overview of what EACH is, what kind of topics are taught during the first study-year at the University of Tartu, what is the nature of the different study-tracks (specialisation during second study-year either in Sweden, Finland or France), what extra activities, such as internship and winter school the EACH programme offers. The paper also gives an explanation on why it is necessary to have such a programme like EACH, and how to be a part of the EACH experience.

One section in the paper is dedicated to the impact of the EACH programme – with the four years that the programme has accepted students, it has reached a lot of countries and the employability rate of the graduates is almost 90%.

This Autumn, the fifth intake of EACH students is starting their studies at the University of Tartu, expanding the blue areas on the map presented above even more.

For more information on the EACH programme, please see the programme’s webpage and also the newly published paper.

18th International Conference on Density-Functional Theory and its Applications

The conference was held with the participation of 190 scientists from 36 countries representing the 5 continents during 22-26 July 2019 in the University of Alicante, Alicante, Spain. One of our group members, Dr. Ali Ghiami-Shomami, presented a poster during this conference. The presented topic, “DFT and TD-DFT Studies of Some Aminoacridines as Matrices in MALDI-MS”, is an effort towards exploring the factors influencing matrix performance in MALDI-MS technique using computational chemistry and in collaborations with our experimentalists. Some visitors appreciated the work and found it interesting. They emphasized that the MALDI-MS technique is very tricky and therefore, finding some insights about it from computational chemistry is valuable. More information about the conference can be found here: www.dft2019.es

MaSC 2019 Workshop and Meeting in Ottawa, Canada

Eliise giving her talk

The 9th Workshop and Meeting of the Users’ Group for Mass Spectrometry and Chromatography (MaSC ) for the study of cultural heritage objects took place on June 3-7, 2019 in Ottawa, the capital of Canada. One of our group members – PhD fellow Eliise Tammekivi – also participated in the workshop and gave an oral presentation at the meeting.

Practical instructions for the analysis of dyes, resins and volatile organic compounds (VOCs)



  • Jennifer Poulin analyzing amber with Thermal Separation Probe (TSP)


  • Dr. Gregory D. Smith presenting a device that can turn even a small sample into a fine powder.

The workshop of MaSC 2019 took place in the Canadian Conservation Institute (CCI) and Parks Canada, where the Thermal Separation Probe (TSP) was presented as a novel device for thermal desorption and „slow pyrolysis“ analyses in gas chromatography-mass spectrometry (GCMS) by the leading researchers in the study of cultural heritage materials. With the instructions from Jennifer Poulin (CCI) the participants were able to conduct the analysis of dyes and identify natural resins by the help of AMDIS  software. With instructor Dr. Gregory D. Smith (Indianapolis Museum of Art at Newfields) participants could perform evolved gas analysis of museum exhibition materials once again with TSP and GCMS.

Topics from fish oil in paintings to the interpretation of highly complex GCMS data

The Meeting of MaSC 2019 took place in the National Gallery of Canada. Presentations were given by the world’s leading analysts about the GCMS analysis of art and historical artifacts. For example, Kate Fulcher (British Museum) talked about the complications of identifying black liquids applied to ancient Egyptian coffins and Corina Rogge (The Museum of Fine Arts Houston) about the utilization of fish oil containing house paints to artists’ paintings in economically difficult times. Additionally, Michael Schilling and Henk van Keulen presented the wonderful advantages of using AMDIS software and ESCAPE for the identification of compounds in complex and small cultural heritage samples. Also, it was Eliise’s first full talk at an international conference, where she presented our groups’ work on the topic „Quantitative analysis of binders in cultural heritage objects“. Specifically, she presented the comparison of four common derivatization procedures in the field of cultural heritage for the quantitative GCMS analysis of oils. For the opportunity to attend the workshop and meeting she would like to thank the organizers of MaSC 2019 and Dora Pluss scholarship (Archimedes).

Short Courses for EU FT-ICR MS staff and students’ community: Ion-molecule reactions: fundamental and analytical aspects.

At the end of June, on 25-27th, two PhD fellows from our group Pilleriin and Eliise attended FT-ICR-MS short course, this time locating in Rome, Italy. Three-days course included both lectures from FT-ICR experts like Jevgeny Nikolaev, Maria Elisa Crestoni, Simonetta Fornarini, and hands-on lab practices. The central theme for the short-course was ion-molecule reactions. During these days, attendees were able to see how ion-molecule reaction experiments are conducted in the University of Sapienza, also get tutorial on how to process all of this extensive data from this process. The FT-ICR used in Sapienza is a 4.7 T Bruker Apex II instrument.

EU_FT-ICR-MS summer school and short course series is altogether a four-year-long project, which aim is to bring together all the scientist using FT-ICR all over Europe and promote the usage of this instrument. During this program 2018-2021, it is also possible to submit your project to use any of the FT-ICR instruments provided in this community.

48th International Symposium on High-Performance Liquid Phase Separations and Related Techniques

Between the 16th to 20th of June our group presented itself in HPLC 2019 in Milan. It was a 5-daylong and intense learning opportunity with more than 300 speakers and around 500 posters.

Topics ranged from fundamentals of HPLC, miniaturization to different omics, pharmaceutical analysis and innovative technologies (can HPLC have a FID as a detector?). For the first time, a whole section was dedicated to 3D printing technologies – a technique that is used to build 3 dimensional separation modules: for example, fascinating talks on using 3D printing to do liquid chromatography in 3 dimensions.

The conference gala dinner was held at the beautiful central courtyard of University of Milan under relieving cool evening sky opposing the hot temperatures of the day. HPLC 2019 also had two new additions that hopefully will become annual traditions: Separation Science Slam and HPLC Tube, offering an opportunity for scientists to express their love for their work in modern ways. The competitions were extremely creative and both the audience and participants were thoroughly enjoying the events. Participants from our analytical chemistry chair gave multiple contributions to the conference.

Ecstasy content in tablets is uneven

Max giving his talk

Max Hecht, MSc, presented an oral presentation on the evaluation of MDMA (also known as ecstasy and  ‘Molly’) content in 412 tablets and dissolution properties in 247 tablets, collected in the UK in the time period of 2001-2018. It was found that there are no physical tablet characteristics which correlate to dissolution rate classification, hence no way of users knowing a priori whether tablets were more likely to be fast or slow-releasing. Further, large within-batch variation in the dose and also dissolution rate was observed, giving the combined result of increasing significantly the danger of over-dosing.

Standard substance free quantification in LC/ESI/MS

Anneli giving her talk

Dr. Anneli Kruve presented the recent work of her group on standard substance free quantification of metabolites in green tea samples. In the metabolomics studies, the standard substances for all detected and identified metabolites are hardly ever available. The peak areas obtained from LC/HRMS analysis are also generally usable as different compounds ionize with vastly different ionization efficiencies; the differences may reach 100 million times. With the aid of ionization efficiency predictions, this shortcoming can be overcome and the absolute concentrations estimated. The current prediction accuracy for the green tea metabolites is 1.7 times, which allows comparison of different tea samples and also the identification of the samples with different origin. Importantly, the standard substance free quantitation allows transferring quantitative data from one lab to another. Anneli has also summarized the current status of standard substance free quantitation for the last issue of LCGC. You can find out more about it from kruvelab.com and quantem.co.

Novel eluent additives diversify analyst´s toolkit

Ruta giving her talk

Ruta Veigure, MSc, showed that fluoroalcohols, such as perfluoropinacol (PP) and 1,1,1,3,3,3-hexafluoro-2-methyl- 2-propanol (HFTB), are very useful alternatives to common eluent additives in RP HPLC-MS analysis, acting, among other effects, as weak ion-paring reagents. Novel eluent additives influenced elution of protonated bases by significantly improving analyte’s retention on C18 stationary phase as well as reduce the retention of acidic analytes, which are deprotonated. A comparison was performed to commonly used ammonium acetate and ammonium bicarbonate mobile phase additives. Her research will be rather influential for the analysis of pharmaceuticals, from whom the majority are basic.

Revolutionalizing pH measurements

Prof. Ivo Leito presented a poster introducing a conceptually new approach of measuring pH of mixed-solvent liquid chromatography (LC) mobile phases: the pHabs approach. The new approach is based on the recently introduced unified pH scale (pHabs scale), which enables direct comparison of acidities of solutions made in different solvents or solvents mixtures based on chemical potential of the proton in the solutions. The viewers praised the fact that real numerical values are now available showing how different the conventional pH values are from pHabs, as well as the educative aspect of the whole endeavour. Some visitors were eager to start immediately applying pHabs in their own work.

This work is part of a larger endeavor – to promote a wider usage the unified pH scale (pHabs) by the research and technology communities, which is currently in progress via the UnipHied. The UnipHied project is funded from the EMPIR programme (project 17FUN09) co-financed by the Participating States and from the European Union’s Horizon 2020 research and innovation programme.

  • Ivo presenting his poster
  • Asko presenting his poster

Automate what can be automated in method validation

Dr. Asko Laaniste introduced the progress on ValChrom, a software for the automation of chromatographic method validation. The development of ValChrom is ongoing and feedback is being gathered from potential users in different fields of chromatography in order to adapt to real needs (contact at valchrom@ut.ee). Feedback from viewers cemented the understanding of the problem that often validation is done in spreadsheets and textual software, that are prone to error. Viewers of the poster approved the endeavour for aiming to help small and medium-sized laboratories that do not have an affordable alternative. They were equally excited to promote the software further to their colleagues in the validation department.

New publication – Comparison of derivatization methods for the quantitative gas chromatographic analysis of oils

Often paints contain oils that bind together the components (pigments, fillers, etc) of the paint. Analysis of these oils requires derivatization, but which derivatization method is the best for a quantitative approach?

The work on this topic began with the need of our cultural heritage group to have a routine method for the determination of fatty acid composition of oils with gas chromatography (GC). The analysis of oils with GC requires derivatization and for this a wide variety of procedures have been applied. It turned out there are only few comparisons of derivatization methods in the literature and all are quite limited by scope. For that reason, it was decided to explore this important topic comprehensively and, importantly, in the terms of absolute (not relative) quantification.

A member of our group – PhD student Eliise Tammekivi – implemented four common and well-known derivatization procedures to perform the absolute quantification of fatty acids with GC-MS and GC-FID. The four compared derivatization methods were: (1) methylation with m-(-trifluoromethyl)phenyltrimethylammonium hydroxide (TMTFTH), (2) two-step derivatization with sodium ethoxide (NaOEt) and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), (3) two-step derivatization with KOH and BSTFA and (4) acid-catalyzed methylation (ACM).

This study has now been completed and the results have been published in the journal Analytical Methods by E. Tammekivi, S. Vahur, O. Kekišev, I. D. van der Werf, L. Toom, K. Herodes and I. Leito. In the publication, a comprehensive and wide-scale quantitative comparison of the four derivatization methods is presented. The results demonstrate that methylation with TMTFTH is the least work-intensive and most accurate derivatization method – both in terms of reproducibility and derivatization efficiency (yield).  For further information see: Analytical Methods, 2019, 11, 3514 – 3522

67th ASMS Conference on Mass Spectrometry and Allied Topics

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

  • Piia presenting her poster
  • Jaanus presenting his poster

Piia presented her results on “Unifying ionization efficiencies: a quantitative comparison of diverse data sets and validation of prediction models” as a poster and there was a great interest in her topic and fruitful discussions about the findings retrievable from the unified datasets.

I presented the results on “Standard Substance Free Quantification of LC/ESI/MS on the Example of Pesticides in Cereal”. Although my poster was scheduled on the last day there was remarkable interest in our topic. Furthermore, future collaborations were arranged to test out our Quantem approach on datasets from different fields, metabolomics to the vaping industry.

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.