Measurement uncertainty online course 2020: highest ever completion rate: 55%!

On May 12, 2020 the on-line course (MOOC) Estimation of measurement uncertainty in chemical analysis offered by University of Tartu finished successfully.
Eventually altogether 843 people registered (270 in 2014, 489 in 2015, 757 in 2016, 363 in 2017, 521 in 2018, 590 in 2019) from 95 countries (a number of participants joined after the start of the course). 600 participants actually started the course (i.e. tried at least one graded test at least once) and out of them 464 successfully completed the course (141 in 2014, 169 in 2015, 308 in 2016, 148 in 2017, 358 in 2018, 238 in 2019). The overall completion rate was 55% (52% in 2014, 34% in 2015, 40% in 2016, 41% in 2017, 42% in 2018, 40% in 2019). The completion rate of participants who started the studies was 77% (67% in 2014, 60% in 2015, 67% in 2016, 68% in 2017, 61% in 2018, 62% in 2019). The completion rate this year is the best we have seen and can be considered excellent 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 during the course period the overall number of forum posts was close to 600 (!) (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 2021.

 

Our collection of acidity and basicity data in non-aqueous media has been updated!

The collections of experimental acidity and basicity data in non-aqueous media measured by our group are now up to date on our Chair of Analytical Chemistry webpage. 

Both tables include the compounds name, CAS number and SMILES code. The acidity collection contains 190 compounds, where the compounds available experimentally measured pKa in acetonitrile (MeCN) and pKip in 1,2-dichloroethane (DCE) are given. The pKa in DCE is calculated/estimated based on pKip value. 

The basicity data collection includes 353 compounds and their pKip in tetrahydrofuran (THF) and in DCE. The pKa values in MeCN were re-evaluated taking into account all (close to 700) measurements of 279 bases. Therefore, these pKa values can be considered the most reliable pKa values measured in MeCN available!

Measurement Uncertainty online course: 828 participants from 92 countries!

On Tuesday, March 24, 2020 the web course Estimation of Measurement Uncertainty in Chemical Analysis was launched the seventh time as a MOOC (Massive Online Open Course)!

Currently 828 participants from 92 countries are registered – the largest audience the course has ever had! 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. 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 them. These tests are available to registered participants via the Moodle e-learning platform.

This course is run under the umbrella of the Estonian Center of Analytical chemistry (https://www.akki.ee/) and forms a part of the measurements and chemical analysis related master programmes at UT: Applied Measurement Science (https://ams.ut.ee/) and Excellence in Analytical Chemistry (https://www.analyticalchemistry.eu/).

 

Tartu City Government acknowledged the organizers of Eurachem 2019!

On the 18th of February, the City Government of Tartu acknowledged the organizers of 14 international conferences that took place last year in Tartu, Estonia.

Mayor Urmas Klaas said that the high-level international conferences make Tartu visible in the field of conference tourism. In the future, the number of these well-organized conferences could be even higher, when Tartu becomes the European Capital of Culture in 2024 and additional flights from Tartu start to operate.

One of the acknowledged conferences was the Eurachem Workshop and General Assembly 2019, which was organized by the Estonian Center of Analytical Chemistry (ECAC)

Congratulations to the main organizer Riin and her team – Ivo, Anneli, Asko, Koit, Hanno, Jaanus, Pilleriin, Eliise and Siiri from our Analytical Chemistry Group for the well-deserved recognition! 

The secrets of two mummies have been unravelled

PLOS ONE has recently published a multidisciplinary paper on two Egyptian child mummies lead and participated by the members of our group. The team of 19 experts unravelled the secrets of two Graeco-Roman child mummies by applying most recent analytical techniques from archaeology, forensic sciences, analytical chemistry, medicine, entomology, and genetics. This is one of the most extensive multidisciplinary study of ancient mummies and the paper is free to download here.

Measurement Uncertainty online course, Mar 24 – May 5, 2020: Registration is open!

The 2020 edition of the web course (MOOC) Estimation of Measurement Uncertainty in Chemical Analysis will be running during Mar 24 – May 5, 2020. Registration is open!

The full course material (as well as the registration link) is accessible from the web page https://sisu.ut.ee/measurement/uncertainty. The course materials include videos, schemes, calculation files and numerous self-tests (among them also full-fledged measurement uncertainty calculation exercises) and examples. Almost all areas of analytical chemistry are addressed, ranging from simple titrations to sophisticated instrumental analysis, such as determining pesticide residues by LC-MS.

In order to pass the course, the registered participants have to take six graded tests and get higher than 50% score in every graded test. These tests are available to registered participants via the Moodle e-learning platform. Participants who successfully pass the course will get a certificate from University of Tartu. A digital certificate of completion is free of charge. A certificate of completion on paper can be requested for a fee of 60 euros.

You are welcome to distribute this message to potentially interested people!

 

Highly Acidic Conjugate‐Base‐Stabilized Enantioselective Carboxylic Acid Catalysts

We recently had the pleasure of collaborating with the group of Daniel Seidel (University of Florida) in the field of enantioselective acidic catalysis. Prof. Seidel and his co-workers have developed Highly Acidic Conjugate‐Base‐Stabilized Enantioselective Carboxylic Acid Catalysts that are able to catalyze oxa‐Pictet–Spengler Reactions with Ketals. Our task in this endeavor was determining the acidity of the catalysts involved and elucidating the effect of the different elements of its substitution scheme on acidity. The main outcome is summarized in the scheme on the left. As can be seen, the most acidifying element is the substituted thiourea moiety, leading to one of the catalysts – the rightmost molecule. The findings strongly suggest that a key to the high acidity is the intramolecular hydrogen bond stabilizing the anion of the acid catalyst. These same substituents are also instrumental in the enantioselective catalytic ability of these catalysts.

This work has been published in Angew. Chem. Int. Edit. 2019.

Celebrating Christmas with our Analytical Chemistry family

Last week, the members of our Analytical Chemistry group celebrated Christmas together. 

After the traditional and tasty Christmas dinner, the not so traditional games took place. Everyone was dived into five teams. All of the teams had the same five tasks – they had to put their main senses to the test. But of course, the tasks required some additional knowledge of chemistry. 

The tasks were the following: identify common laboratory objects in a self-made and a not see-through “glove box” (touch); recognize the sounds of various laboratory machines, including the coffee maker (hearing); notice molecules and atoms in a drawing (sight); determine the concentrations of sugar solutions by tasting sugar solutions with known concentrations (taste); identify various alcohols and fragrant compounds by their aroma. The games of senses ended with a fun quiz.

                                   Touch

HearingSightTasteSmell

Wishing you happy holidays and a wonderful new year from our Analytical Chemistry group!

Jaanus Liigand was awarded the 1st prize in Estonian National Contest for University Students for his doctoral thesis

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 contentpH 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!

New non-invasive approach to analyze textile fibers

Another new method development in our group has been assembled into a publication. Article by Pilleriin Peets (on the picture), Karl Kaupmees,  Signe Vahur, and Ivo Leito in the journal of Heritage Science introduces non-invasive approach to identify all kinds of different textile fibers using reflectance-FT-IR spectroscopy and chemometry. In this work 61 single-component textile pieces were analyzed, 4000 spectra were recorded and all in all 16 different textile fiber types were characterized. As reflectance-FT-IR spectroscopy is not widely used to analyze samples with an uneven surface, in our best knowledge, this article provides the largest collection of r-FT-IR spectra from textile fibers that is recorded and published. All the r-FT-IR spectra from different fiber classes are now available for other scientists, conservators, museum workers and industries to use!

PCA classification graph of different textile fiber classes. Peets, P., Kaupmees, K., Vahur, S., Leito, I. Reflectance FT-IR spectroscopy as a viable option for textile fiber identification. Herit Sci  7, 93 (2019)