New publication: determining water content in lignin using ATR-FTIR

Shrikant performing the FTIR measurements

We are delighted to share that our latest article titled “A quantitative approach to determine water and moisture content of different types of lignin using attenuated total reflectance Fourier transform infrared spectroscopy combined with partial least squares regression” has been published in the journal of Biofuels, Bioproducts and Biorefining (Volume 20, 2026). The article was authored by Shrikant Shivaji Pawade, together with Dr Martin Vilbaste, Andres Siiman, Dr Lauri Toom, Associate Professor Koit Herodes, and Professor Ivo Leito. The article is Open Access and available online; click here to access it.

The study presents a quantitative methodology for determining water and moisture content in diverse lignin types using ATR-FTIR spectroscopy combined with partial least squares regression, with vapourisation–coulometric Karl Fischer titration (vap-C-KFT) and gravimetric methods used as reference techniques. In addition, the work introduces a sigmoid curve approach to temperature optimisation for vap-C-KFT and evaluates sampling and modelling uncertainties, thereby providing practical insights for reliable lignin characterisation. The robustness of the method was assessed by validation against vap-C-KFT, oven drying (7 h and 48 h), and freeze-drying, utilising diverse lignin types (Kraft, Dealkaline, and Lignova Fibenol) and achieving RMSEP values ranging from 0.33 to 1%.

The results demonstrate that ATR-FTIR combined with chemometrics modelling can provide a rapid, simple, and cost-effective alternative to conventional methods, while maintaining good accuracy across diverse lignin types.

Measurement Uncertainty MOOC: Registration is now open!

The 2026 edition of the web course (MOOC) Estimation of Measurement Uncertainty in Chemical Analysis will run from March 24 to May 6, 2026. Registration is now open!

The full course material (as well as the registration link) is accessible from the web page. 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 volumetric operations and titrations to sophisticated instrumental analysis, such as determining pesticide residues by LC-MS. Efforts are made in the course to address also such uncertainty sources encountered in chemical analysis that are difficult to quantify, e.g. uncertainty due to possible interference effects (incomplete selectivity), analyte losses, etc.

In order to pass the course, the registered participants have to take six graded tests and get a 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 the 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 62 euros.

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

Our LC-MS validation activities at the IUPAC-DSM LC-MS validation workshop

Riin Rebane, Asko Laaniste and Ivo Leito participated on 10-11.12.2025 in the Joint IUPAC-DSM Workshop on LC-MS method validation and performance, organised jointly by the IUPAC’s Division of Analytical Chemistry and the Mass spectrometry division (DSM) of the Italian Chemical Society.

Riin presenting

Riin presented the opening keynote of the event titled “Principles of method validation”. Her presentation reframed LC-MS method validation as a risk-management process rather than a checklist of validation characteristics. By zooming out to the method’s intended purpose, each validation characteristic is linked to the specific risks it is designed to control. This view allows to build evidence that the method performs reliably under real-world conditions and is truly fit for purpose and produces results with known confidence.

 

 

Ivo’s talk “What are the issues encountered in the real world? Lessons learned form an online validation course” presented an analysis of the main issues brought up by the participants of the nine editions of an online LC-MS method validation course (https://sisu.ut.ee/lcms_method_validation/). The analysis of 2640 course forum posts and 336 participant feedback submissions revealed that practitioners struggle a lot with calculations and spreadsheet software, which diverts effort from real “analytical hemistry” issues.  

Asko leading the ValChrom session

Asko’s session “ValChrom open-access online validation software” was a workshop in the true sense of the word: a hands-on session on the online validation software ValChrom developed at UT. Participants had instant access to the software freely available in web and demo materials. Asko walked them through the whole process of ValChrom from start to finish, from defining analytes to customizing experimental plan with AI and finishing with automatically generated DOCX file with the whole validation data in it. ValChrom’s Design of Experiements (DoE) capabilities were also covered and it was nice to see that throughout the two days a big number of presentations also involved DoE one way or another, indicating a rising need for such tools.

All in all, the contributions of our team were highly appreciated, indicated by numerous questions, both during sessions and (especially) during coffee breaks.

 

 

Measurement uncertainty online course 12th run has successfully finished!

On May 14, 2025, the on-line course (MOOC) Estimation of measurement uncertainty in chemical analysis offered by the University of Tartu finished successfully. Eventually, altogether 1061 people registered from 100 countries. 525 participants actually started the course (i.e. tried at least one graded test at least once). The overall completion rate was 29%. The participation rate was 49% this year. The completion rate of the participants who started the studies was 59%, with 307 successfully finished participants. This result is quite stable during the 12 runs. This result can be considered good for a MOOC, especially for one that has quite difficult calculation exercises, which need to be done correctly with a limited number of attempts to complete the course. All statistics during the 12 years can be found in the table below. 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 above 400 (!) (overall number of posts, both from participants and from teachers) and the forums are still active and posts are still coming in. We want to thank all participants for helping to make this course a success! We plan to repeat this course again in Spring 2026!

Measurement Uncertainty online course: 1061 participants from 100 countries!

On Tuesday, March 25, 2025 the web course Estimation of Measurement Uncertainty in Chemical Analysis was launched the twelfth time as a MOOC (Massive Online Open Course)!

Altogether 1061 participants from 100 countries are registered – the largest number of participants the course has ever had! In the map presented above, the yellow color marks the countries form where participants come. True, the map is coarse and some countries are small. Therefore, not all countries are visible. We are very happy, that we have 9 participants also from Ukraine this year. Slava Ukraini!
Registration for this run is closed. But good news: if you did not manage to register this time, you are welcome to register for the 2026 edition of the course.

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 Excellence in Analytical Chemistry (https://www.analyticalchemistry.eu/) Erasmus Mundus master’s programme.

Measurement Uncertainty online course: registration is now open!

The 2025 edition of the web course (MOOC) Estimation of Measurement Uncertainty in Chemical Analysis will be running from March 25 to May 7, 2025. Registration is now open!

The full course material (as well as the registration link) is accessible from the web page. 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 volumetric operations and titrations to sophisticated instrumental analysis, such as determining pesticide residues by LC-MS. Efforts are made in the course to address also such uncertainty sources encountered in chemical analysis that are difficult to quantify, e.g. uncertainty due to possible interference effects (incomplete selectivity), analyte losses, etc.

In order to pass the course, the registered participants have to take six graded tests and get a higher than 50% score on 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 the 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!

Measurement uncertainty online course 11th run has successfully finished!

On May 09, 2024 the on-line course (MOOC) Estimation of measurement uncertainty in chemical analysis offered by the University of Tartu finished successfully.

Eventually altogether 1047 people registered from 104 countries. 655 participants actually started the course (i.e., tried at least one graded test at least once). The overall completion rate was 38%. The participation rate was this year 63%. The completion rate of the participants who started the studies was 61%, with 398 successfully finished participants. This result is quite stable during the 11 runs, showing also a small improving tendency compared to years after the COVID pandemic. This result can be considered good for a MOOC, especially for one that has quite difficult calculation exercises, which need to be done correctly with limited number of attempts for completing the course. All statistics during the 11 years can be found in the table below.

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 around 300 (!) (overall number of posts, both from participants and from teachers) and the forums are still active and posts are still coming in.

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

We plan to repeat this course again in Spring 2025 with a new breath in the course appearance!

Measurement Uncertainty online course: 1048 participants from 104 countries!

On Tuesday, March 19, 2024, the web course Estimation of Measurement Uncertainty in Chemical Analysis was launched for the eleventh time as a MOOC (Massive Online Open Course)!

Altogether 1048 participants from 104 countries are registered – the largest number of countries the course has ever had! In the map presented above, the yellow color marks the countries from where participants come. True, the map is coarse and some countries are small. Therefore, not all countries are visible. We are very happy, that we have 16 participants also from Ukraine this year. Slava Ukraini!

The entire 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/).

 

Measurement Uncertainty online course, March 19 – May 2, 2024: Registration is open!

The 2024 edition of the web course (MOOC) Estimation of Measurement Uncertainty in Chemical Analysis will be running from March 19 to May 2, 2024. Registration is now open!

The full course material (as well as the registration link) is accessible from the web page. 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 volumetric operations and titrations to sophisticated instrumental analysis, such as determining pesticide residues by LC-MS. Efforts are made in the course to address also such uncertainty sources encountered in chemical analysis that are difficult to quantify, e.g. uncertainty due to possible interference effects (incomplete selectivity), analyte losses, etc.

In order to pass the course, the registered participants have to take six graded tests and get a 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 the 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!

 

Measurement uncertainty online course 9th run has successfully finished!

On May 13, 2022 the on-line course (MOOC) Estimation of measurement uncertainty in chemical analysis offered by University of Tartu finished successfully.

Eventually, altogether 851 people registered from 103 countries. 405 participants actually started the course (i.e. tried at least one graded test at least once). The overall completion rate was 28%. This, as well as the participating rate was the lowest (48%) we have seen. However, the completion rate of the participants who started the studies was 59% with 239 successfully finished participants. Although lower than we have previously see, this result can still be considered very good for a MOOC, especially for one that has quite difficult calculation exercises, which need to be done correctly with limited number of attempts for completing the course. All statistics during the 9 years can be found in the table below.

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 over 500 (!) (overall number of posts, both from participants and from teachers) and the forums are still active and posts are still coming in.

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

We plan to repeat this course again in Spring 2023.