Université de Fribourg

Resolution limit of taylor dispersion: an exact theoretical study

Taladriz-Blanco, Patricia ; Rothen-Rutishauser, Barbara ; Petri-Fink, Alke ; Balog, Sandor

In: Analytical Chemistry, 2020, vol. 92, no. 1, p. 561–566

Taylor dispersion is a microfluidic analytical technique with a high dynamic range and therefore is suited well to measuring the hydrodynamic radius of small molecules, proteins, supramolecular complexes, macromolecules, nanoparticles and their self- assembly. Here we calculate an unaddressed yet fundamental property: the limit of resolution, which is defined as the smallest change in the...

Université de Fribourg

A new procyanidin B from Campylospermum zenkeri (Ochnaceae) and antiplasmodial activity of two derivatives of (±)-serotobenine

Mbabi Nyemeck II, Norbert ; Ngono Bikobo, Dominique Serge ; Zintchem, Auguste Abouem A. ; Schäfer, Eva-Maria ; Bochet, Christian G. ; Pegnyemb, Dieudonné Emmanuel ; Koert, Ulrich

In: Natural Product Research, 2017, vol. 31, no. 24, p. 2875-2884

Phytochemical investigation of the stem bark of Campylospermum zenkeri led to the isolation of five known compounds: (Z,Z)-9,12-octadecadienoic acid (1), serotobenine (2), agathisflavone (3), lophirone A (4) and lophirone F (5), together with a new derivative of procyanidin B, a catechin dimer named zenkerinol (6). Serotobenine (2) is structurally related to decursivine which shows moderate...

Haute Ecole d'Ingénierie

Profiling of anionics metabolites using CE-qTOF-MS with bare fused silica capillaries = Profil de métabolites anioniques par CE-qTOF-MS au moyen de capillaires

Meyrat, Cindy

Mémoire de diplôme HES : Haute Ecole d'Ingénierie, 2008.

Objective: Metabolomics approaches have become an important strategy to gain insight into various aspects of metabolism. However, the comprehensive coverage of all cellular metabolites presents formidable challenges because of the immense range of structures and chemical properties. Capillary electrophoresis coupled to mass spectrometry is considered a promising technique for the profiling of...

Haute Ecole d'Ingénierie

Influences of different HPLC phases on separation of synthetic peptides = Étude de l'influence de différents HPLC-Phasen sur la séparation des peptides de synthèse.

Gaudard, Olivier ; Cicciarelli, Romolo (Dir.)

Mémoire de diplôme HES : Haute Ecole d'Ingénierie, 2007.

Ziel Verschiedene HPLC und UPLC Phasen wurden getestet hinsichtlich der Suche nach einem allgemeinen Ansatz für die Trennung von synthetischen Peptiden. Resultate Die Peptide von 20 Aminosäuren ± 2 Glyzinien, wurden die besten Trennung Ergebnisse mit der UPLC bei pH 3 mit einer Perchorat Lösung 100 mM erreicht, aber die HILC Phase kann mit einer etwas geringerer Trennleistung (Rs 1.06...