Agnes Heering successfully defended her PhD thesis on experimental realization of the unified pH scale
On December 6, 2017 Agnes Heering successfully defended her PhD thesis titled Experimental realization and applications of the unified acidity scale.
Her work literally redefines the way the pH of non-aqueous and mixed aqueous solution is understood and measured. The main focus of the experiments was on validating the measurement approach and measuring the unified pH values, i.e. pHabs values, of HPLC mobile phases (eluents). Her work introduces a conceptually new approach of measuring pH of mixed-solvent liquid chromatography (LC) mobile phases and has been published in the Analytical Chemistry journal: Unified pH Values of Liquid Chromatography Mobile Phases. Anal. Chem. 2015, 87, 2623–2630.
Mobile phase pH is very important in LC, but its correct measurement is not straightforward and all commonly used approaches have deficiencies. The new and fundamentally correct approach developed by Agnes enables direct comparison of acidities of solutions made in different solvents, based on chemical potential of the proton in the solutions.
The work by Agnes represents the first experimental realization of the pHabs concept using differential potentiometric measurement for comparison of the chemical potentials of the proton in different solutions (connected by a salt bridge), together with earlier published reference points for obtaining the pHabs values (referenced to the gas phase) or pHabsH2O values (referenced to the aqueous solution). The liquid junction potentials were estimated in the framework of Izutsu’s three-component method.
She determined the pHabs values for a number of common LC and LC-MS mobile phases and formed a self-consistent pHabs scale. This scale enables for the first time direct comparison of acidities of any LC mobile phases: with different organic additives, different buffer components etc. Agnes has developed a possible experimental protocol of putting this new approach into chromatographic practice and has tested its applicability. She has demonstrated that the ionization behavior of bases (cationic acids) in the mobile phases can be better predicted by using the pHabsH2O values and aqueous pKa values than by using the alternative means of expressing mobile phase acidity. Description of the ionization behavior of acids on the basis of pHabsH2O values is possible if the change of their pKa values with solvent composition change is taken into account.
The defence was successful in every respect. Agnes presented very well, answered questions confidently and convincingly demonstrated to everyone that she is really on top of this whole matter.
(Photo: Agnes Heering and prof. Peeter Burk, the chairman of the defence committee, during defence)
We are glad to announce that the 2018 admission is officially open to the 4th intake of the Excellence in Analytical Chemistry (EACH) Erasmus Mundus Joint Master Degree programme!
This international two-year joint master degree programme educates specialists in analytical chemistry well qualified to work in industry (food, pharmaceutical, materials, energy, etc), chemical analysis laboratories (environment, food, health, etc) and research (developing new analysis devices or new analysis methods) worldwide. EACH provides knowledge and practical skills in both fundamental and applied aspects of modern analytical chemistry. Practical internship placement in industry or laboratories is an important part of the training.
The programme is suitable both for students who have finished their bachelor’s studies and want to continue in master’s studies, as well as for working analytical chemistry practitioners wishing to spend couple of years to bring their knowledge and skills to a new level.
The programme features generous scholarships as detailed in the Scholarships and tuition fees page.
The programme is taught by four universities: University of Tartu (UT, coordinator), Estonia; Uppsala University (UU), Sweden; University Claude Bernard Lyon 1 (UCBL), France; and Åbo Akademi University (AAU), Finland. The language of instruction is English, but students will also learn to communicate in one of the languages of the countries involved.
The online application form, admission requirements, deadlines, list of necessary documents, instructions/explanations, as well as contact data for questions are available from the EACH Admission information page.
We wish you all the success in applying!
During Nov 20 to Dec 1 we had the pleasure to host visiting scholar, prof. Todd Pagano from the Rochester Institute of Technology (RIT), USA. He conducted a two week-intensive course Principles and applications of fluorescence spectroscopy.
In this course, students reviewed the principles of fluorescence spectroscopy, were introduced to the impact of photophysical phenomena on fluorescence data, and discussed new directions of fluorescence in analytical chemistry. Techniques in multidimensional fluorescence spectroscopy with chemometric analysis were highlighted, especially in the context of novel applications in environmental and related fields.
The course consisted of lectures, seminars, tutorial sessions and a lab practical. The latter was specifically set up for this course by prof. Pagano and was very much appreciated by students. The analysis that was carried out was determination of caffeine in beverages by fluorescence quenching.
Altogether 23 students (out of them 13 EACH students) participated in the course and their feedback was overwhelmingly positive.
Prof. Pagano is a passionate educator. He was the director of the Laboratory Science Technology program at Rochester Institute of Technology’s National Technical Institute for the Deaf, which is a unique science programme, specifically designed for deaf students. He was named “2012 U.S. Professor of the Year” by the Council for Advancement and Support of Education and the Carnegie Foundation for the Advancement of Teaching.
Besides the EACH Erasmus Mundus JMD, prof. Pagano’s visit was funded as part of a project by the US Fulbright Specialist programme.
(Images: top left, prof. Pagano working with students in the lab; right: prof. Pagano lecturing; bottom left: prof. Pagano setting up lab practical)
On Tuesday, November 28, 2017 the web course LC-MS Method Validation was launched for the second time as a MOOC (Massive Online Open Course). There are 423 registered participants (by more than 100 more than in 2016) from 71 countries, ranging from Bolivia to Indonesia and from Sweden to Tanzania. Image on the left shows the countries where the participants come from.
This is a practice-oriented on-line course on validation of analytical methods, specifically using LC-MS as technique. The course introduces the main concepts and mathematical apparatus of validation, covers the most important method performance parameters and ways of estimating them. The LC-MS validation course is delivered by a team of 8 teachers, each with their own specific area of competence. This way it is expected to offer the best possible knowledge in all the different subtopics of analytical method validation.
The full set of course materials is accessible from the web page https://sisu.ut.ee/lcms_method_validation/. The course materials include videos, schemes, calculation files and numerous self-tests (among them also full-fledged calculation exercises). In order to pass the course the registered participants have to take all tests and get higher than 50% score from each of them. 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.
It is planned to run this course as MOOC again in autumn 2018.
(Image: Wikimedia Commons)
The Analytical chemistry group at UT recently received a very pleasant and well-deserved recognition: the paper MALDI‐FT‐ICR‐MS for Archaeological Lipid Residue Analysis J. Mass Spectrom. 2017, 52, 689-700 led by research fellow Dr Ester Oras was selected by the editorial board as the cover article for the Oct 2017 issue of the Journal of Mass Spectrometry!
Ester’s research demonstrates that tiny (and to a large extent degraded) food remains on ceramic potsherds, dating back many hundreds of years, can still tell interesting stories about the food practices of our ancestors. The key to these results is clever usage of high-resolution FT-MS with MALDI ion source.
The developed methodology is expected to lay foundation to further studies of ancient food practices in Europe.
(Photo on the left: cover of the Oct 2017 issue of the Journal of Mass Spectrometry; photo on the right: Ester Oras)