On Oct 26, 2018 Ivo Leito gave a presentation titled Analytical chemistry education activities at University of Tartu at the EcoBalt 2018 conference in Vilnius (Lithuania).

The presentation contains information about the on-line courses LC-MS Method Validation and Estimation of Measurement Uncertainty in Chemical Analysis, as well as the recently published tutorial reviews (Validation I, Validation II, LoD I, LoD II) that form the basis of the LC-MS Method Validation course.

The presentation also addresses the international master’s programmes Applied Measurement Science and Excellence in Analytical Chemistry at University of Tartu.

The last part of the talk is devoted to the Eurachem 2018 General Assembly and Workshop that will take place in Tartu on May 20-21, 2018. The topic of the workshop is “Validation of targeted and non-targeted methods of analysis”.


Validation_of_LC-MS_Methods_Online_CourseWe are glad to announce that the third edition of the online course LC-MS Method Validation is open for registration at the address https://sisu.ut.ee/lcms_method_validation/ !

The course will be offered as a Massive Open On-line Course (MOOC) during Nov 27, 2018 – Feb 08, 2019.

This is a practice-oriented on-line course on validation of analytical methods, specifically using liquid chromatography-mass spectrometry (LC-MS) as technique, mostly (but not limited to) using the electrospray (ESI) ion source. The course will also be of interest to chromatographists using other detector types. The course introduces the main concepts and mathematical apparatus of validation, covers the most important method performance parameters and ways of estimating them. The course is largely based on the recently published two-part tutorial review:

The course materials include lectures, practical exercises and numerous tests for self-testing. In spite of being introductory, the course intends to offer sufficient knowledge and mathematical skills for carrying out validation for most of the common LC-MS analyses in routine laboratory environment. The real-life analysis situations for which there are either examples or self-tests are for example determination of pesticides in fruits and vegetables, perfluoroalkyl acids in water, antibiotics in blood serum, glyphosate and AMPA in surface water, etc. It is important to stress, that for successful validation practical experience – both in analytical chemistry as such and also specifically in validation – is crucial and this can be acquired only through hands-on laboratory work, which cannot be offered via an on-line course.

Participation in the course is free of charge. Receiving digital certificate (in the case of successful completion) is also free of charge. Printed certificate (to be sent by post) is available for a fee of 60 EUR. Registration is possible until the start of the course. The course material is available from the above address all the time and can be used via web by anyone who wishes to improve the knowledge and skills in analytical method validation (especially when using LC-ESI-MS).


This is the range of topics addressed on Aug 31, 2018 as PhD dissertations addressing these topics were defended at UT Institute of Chemistry (lead partner of ECAC) by Sofja Tšepelevitš and Märt Lõkov.

Sofja Tšepelevitš (right on the photo) in her thesis titled Experimental studies and modeling of solute-solvent interactions evaluated and developed approaches for modeling intermolecular interactions in solutions and the resulting macroscopic solute properties. The applicability of the COSMO-RS method to modeling hydrogen bonding in solution was evaluated. COSMO-RS was also evaluated for its ability to predict solvent-solvent extraction. An interesting and novel issue addressed in her work besides conventional structure based property prediction was the possibility to predict liquid-liquid partitioning of solutes with unknown structure.

The thesis of Märt Lõkov titled Basicity of some nitrogen, phosphorus and carbon bases in acetonitrile is focused on obtaining high-quality basicity data (pKa data) of bases of most diverse families and rationalizing their behavior and revealing structure-basicity relationships. Nitrogen bases (N-heterocycles), phosphorus bases (halogen-substituted phosphanes) and carbon bases (substituted pentafulvenes) were included in the work.

Congratulations to both of you!

The research of Sofja and Märt was carried out using the ECAC instrumentation.

Initiated by the University of Tartu, the pan-European research network of fundamental pH Research UnipHied (www.uniphied.eu) started in May 2018.

Why is such network needed? As of now, it is not possible to compare pH values of solutions made in different solvents, as every solvent has its own pH scale. This situation is highly unfortunate, since it causes confusion and inaccuracies into many fields, extending far beyond the specific field of acid-base chemistry. Examples are industrial catalytic processes, food chemistry, liquid chromatograpy, etc. The central goal of UnipHied is to overcome this situation by putting the new theoretical concept of the recently introduced unified pHabs scale on a metrologically well-founded basis into practice.

The most important specific objectives of UnipHied are (1) to develop and validate a reliable and universally applicable measurement procedure that enables the measurement of pHabs; (2) to create a reliable method for the experimental or computational evaluation of the liquid junction potential between aqueous and non-aqueous solutions; (3) to develop a coherent and validated suite of calibration standards for standardizing routine measurement systems in terms of pHabs values for a variety of widespread systems (e.g., industrial mixtures, soils/waters, food products, biomaterials).

The first version of the pHabs measurement procedure has been created by Agnes Heering (Suu) in the framework of her PhD thesis. The main experimental difficulty is evaluation of the liquid junction potential (LJP), which will be thoroughly addressed by UnipHied. The first important steps towards this goal have very recently been made and published as two back-to-back papers: Angew. Chem. Int. Ed. 2018, 57, 2344–2347 and Angew. Chem. Int. Ed. 2018, 57, 2348–2352
The key achievement described in the papers is finding an ionic liquid, namely [N2225][NTf2], that can be used as salt bridge electrolyte and has such properties that two out of three main sources of LJP are eliminated.

The partners of the UnipHied network are LNE (France, coordinator), BFKH (Hungary), CMI (Czech Republic), DFM (Denmark), IPQ (Portugal), PTB (Germany), SYKE (Finland), TÜBITAK-UME (Turkey), Freiburg University (Germany), ANBSensors (United Kingdom), FCiencias.ID (Portugal), UT (Estonia).

UnipHied 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.


A comprehensive comparative validation for two different types of dissolved oxygen (DO) analyzers, amperometric and optical, together with estimation of measurement uncertainty is presented in the recently published article I. Helm, G. Karina, L. Jalukse, T. Pagano, I. Leito, Environmental Monitoring and Assessment 2018, 190, 313.

A number of performance characteristics were evaluated including drift, intermediate precision, accuracy of temperature compensation, accuracy of reading (under different measurement conditions), linearity, flow dependence of the reading, repeatability (reading stability), and matrix effects of dissolved salts. The matrix effects on readings in real samples were evaluated by analyzing the dependence of the reading on salt concentration (at saturation concentration of DO). The analyzers were also assessed in DO measurements of a number of natural waters. The uncertainty contributions of the main influencing parameters were estimated under different experimental conditions. It was found that the uncertainties of results for both analyzers are quite similar but the contributions of the uncertainty sources are different.

The results imply that the optical analyzer might not be as robust as is commonly assumed, however, it has better reading stability, lower stirring speed dependence, and typically requires less maintenance. On the other hand, the amperometric analyzer has a faster response and wider linear range.

(Photo by Lauri Jalukse: measurements of dissolved oxygen concentration with amperometric and optical analyzers at Jordan spring, Karksi-Nuia, Estonia)


Measurement_Uncertainty_MOOC_Successfully_FinishedOn May 14, 2018 the on-line course (MOOC) Estimation of measurement uncertainty in chemical analysis offered by University of Tartu finished successfully.
Eventually altogether 521 people registered (270 in 2014, 489 in 2015, 757 in 2016, 363 in 2017) from 76 countries (a number of participants joined after the start of the course). 358 participants actually started the course (i.e. tried at least one graded test at least once) and out of them 218 successfully completed the course (141 in 2014, 169 in 2015, 308 in 2016, 148 in 2017). The overall completion rate was 42% (52% in 2014, 34% in 2015, 40% in 2016, 41% in 2017). The completion rate of participants who started the studies was 61% (67% in 2014, 60% in 2015, 67% in 2016, 68% in 2017). The completion rates are nicely consistent over the last years and can be considered very good for a MOOC, especially one that has quite difficult calculation exercises, which need to be done correctly for completing the course.

The participants were very active and asked lots of questions. The questions were often very much to the point and addressed things that are really important to analysts in their everyday work. The course has several forums (general and by topic) and the overall number of posts to them during the course period reached almost 300 (!) (overall number of posts, both from participants and from teachers) and the forums are still active and posts are still coming in.

This active participation made teaching of this MOOC a great experience also for us, the teachers. The discussion threads gave a lot of added value to the course and some of them triggered making important modifications to the course materials, even during the course.

We want to thank all participants for helping to make this course a success!

We plan to repeat this course again in Spring 2019.


AKKI infopäev 03.05.18 AKKI_Infopaev_030518äratas ootuspäraselt laialdast huvi ja õnnestus suurepäraselt! Osalejaid oli 57, mis oli ligilähedane maksimaalsele oodatud osalejate arvule. Osalejad olid tõeliselt mitmekesiste taustadega – tööstuste esindajatest süvateadlasteni, laboritöötajatest riigiametnikeni. Oli nii professoreid kui doktorante, laborijuhataid kui omakäelisi analüütikuid.

Ettekannetega olid esindatud AKKI kolm partnerit, samuti ka mõned organisatsioonid, kes on AKKI laboritega edukalt koostööd teinud – Eesti Kunstiakadeemia (koostöö Europa Nostra auhinna pälvinud Rode altari projekti raames) ja OÜ Holz Prof (koostöö tootearenduse raames). Päeva huvitavaim osa oli kahtlemata ringkäik Chemicum’i laborites ja vabas vormis diskussioonid AKKI spetsialistidega.

Osalejatega vesteldes jäi kõlama üldine seisukoht, et selline teadmisi ja aparatuuri koondav ettevõtmine, mida AKKI endast kujutab, on kogu Eesti jaoks väga vajalik. Vestluste käigus tekkisid ka mitmed konkreetsed koostööideed, mille realiseerimine algab lähiajal.


AKKI meeskonnal on rõõm teatada, et on toimumas esimene AKKI võrgustikku tutvustav infopäev.

Ürituse raames on võimalik saada ülevaade AKKI partnerite tegevustest ning koostöövõimalustest. Lisaks on võimalus uudistada ringi Chemicumis ning suhelda meie teadlastega.

Üritus toimub Tartus ja on eesti keeles.

Registreerimine on avatud aadressil http://akki.ut.ee/akki-infopaev/

Every year Estonian University of Life Sciences organises a conference called “Healthy animal and healthy food” where Dr. Riin Rebane made a presentation “Fight against food fraud” which explained the ever-expanding role of analytical chemists in food science. Reasons for food fraud vary, but are almost always for monetary gain and therefore food fraud is in constant progress. One good example is honey analysis, where for decades there has been a change in methods in order to identify whether honey is real or whether it is identified with correct botanical or geographical origin. As a natural product, no two honeys are identical and this makes identification further more challenging for the chemists. One of the possible methods is amino acid analysis since the amino acid content can be like a fingerprint for honeys and in University of Tartu we have analysed few hundreds of Estonian honeys and have seen that that foreign honeys do differ in most cases and also that there is a correlation between the amino acid content and botanical origin. But nevertheless, even this method might not work every time and chemists are looking towards methods such as nuclear magnetic resonance spectroscopy and even DNA-analysis to get better certainty for determining the origin of honey.

The summary based on the presentation was also reported in the newspaper Maaleht.


U_MOOC_Countries_of_Participants_2018On Tuesday, March 27, 2018 the web course Estimation of Measurement Uncertainty in Chemical Analysis was launched the fifth time as a MOOC (Massive Online Open Course)!

Currently more than 450 participants from 70 countries are registered! As was the case in the previous years, the majority of participants are from analytical laboratories. This once again demonstrates the continuing need for training in measurement uncertainty estimation for practicing analytical chemists.

The full course material is accessible from the web page https://sisu.ut.ee/measurement/uncertainty. As is usual, some developments and improvements have been made to the course material. in particular, the description of course organisatsion was improved; more explanations and examples were added on random and systematic effects within short and long term; the typical requirements for determining repeatability and within-lab reproducibility have been clearly outlined; more explanations on the main principles of modifying a model in a modelling approach have been given, together with an example. Some changes are still in the pipeline.

The course materials include videos, schemes, calculation files and numerous self-tests (among them also full-fledged measurement uncertainty calculation exercises). In order to pass the course the registered participants have to pass six graded tests and get higher than 50% score from each of tehm. These tests are available to registered participants via the Moodle e-learning platform.