Refine my results

Document type


Specific Collection


Université de Fribourg

Silver nanoparticle formation in different sizes induced by peptides identified within split-and-mix libraries

Belser, Kirsten ; Slenters, Tünde Vig ; Pfumbidzai, Conelious ; Upert, Grégory ; Mirolo, Laurent ; Fromm, Katharina M. ; Wennemers, Helma

In: Angewandte Chemie International Edition, 2009, vol. 48, no. 20, p. 3661-3664

Split-and-mix libraries are an excellent tool for the identification of peptides that induce the formation of Ag nanoparticles in the presence of either light or sodium ascorbate to reduce Ag+ ions. Structurally diverse peptides were detected in colorimetric on-bead screenings that generate Ag nanoparticles of different sizes, as confirmed by SEM and X-ray powder diffraction studies

Université de Fribourg

Recent advances in tailoring the aggregation of heavier alkaline earth metal halides, alkoxides and aryloxides from non-aqueous solvents

Fromm, Katharina M.

In: Dalton Transactions, 2006, p. 5103 - 5112

This overview on one of the subjects treated in our group deals with the synthesis and study of low-dimensional polymer and molecular solid state structures formed with alkaline earth metal ions in non-aqueous solvents. We have chosen several synthetic approaches in order to obtain such compounds. The first concept deals with the "cutting out" of structural fragments from a solid state structure...

Université de Fribourg

The first two-dimensional polycatenane: a new type of robust network obtained by Ag-connected one-dimensional polycatenanes

Sagué, Jorge L. ; Fromm, Katharina M.

In: Crystal Growth & Design, 2006, vol. 6, no. 7, p. 1566–1568

The two-dimensional structure described here is the first example of a coordination polymer structure consisting of one-dimensional polycatenanes fused via silver ions. It can be derived from simple rings consisting of two silver ions and two ligand molecules.

Université de Fribourg

Silver coordination compounds as light-stable, nano-structured and anti-bacterial coatings for dental implant and restorative materials

Slenters, Tünde Vig ; Hauser-Gerspach, Irmgard ; Daniels, Alma U. ; Fromm, Katharina M.

In: Journal of Materials Chemistry, 2008, vol. 18, p. 5359-5362

Silver coordination polymer chains were deposited on Au(111) as a model surface, as well as on gold alloy and titanium as dental implant and restorative materials. The topography of the surface was analysed on the model substrate and it was found to be a nano-structured crystalline material. In vitro investigations in a flow chamber imitating the oral environment prove the anti-bacterial...

Université de Fribourg

Counterion effect on the formation of coordination polymer networks between AgNO₃ and L (2,2′-oxybis(ethane-2,1-diyl) diisonicotinate) Part 2

Sague, Jorge L. ; Meuwly, Markus ; Fromm, Katharina M.

In: CrystEngComm, 2008, vol. 10, p. 1542-1549

Herein we report the synthesis and characterization by single crystal X-ray diffraction of three new silver(I) complexes {[Ag₂·L₂](NO₃)₂(H₂O)₄} (1), {[Ag₂·L₂](NO₃)₂} (2) and {[Ag₂·L₂](NO₃)₂} (3). Whereas compounds 2 and 3 are...

Université de Fribourg

Amino acids in iron oxide mineralization: (incomplete) crystal phase selection is achieved even with single amino acids

Mantion, Alexandre ; Gozzo, Fabia ; Schmitt, Bernd ; Stern, Willem B. ; Gerber, Yvonne ; Robin, Adeline Y. ; Fromm, Katharina M. ; Painsi, Monika ; Taubert, Andreas

In: The Journal of Physical Chemistry C, 2008, vol. 112, no. 32, p. 12104–12110

Iron oxides are important minerals in biology and materials science. Using biomimetic synthesis, a variety of iron oxides have been fabricated. However, it is still not clear how growth modifiers like amino acids and peptides select different crystal phases of a complex material like iron oxide. The current paper shows that already with single amino acids, (incomplete) crystal phase selection is...

Université de Fribourg

Antimicrobial coatings for implant surfaces

Brunetto, Priscilla S. ; Fromm, Katharina M.

In: Chimia, 2008, vol. 62, no. 4, p. 249-252

Body-foreign materials are used more and more frequently in our lives: joint implants (hips, knees, fingers, etc.), catheters, pacemakers, dental and aesthetic implants, etc. The increasing numbers of patients requiring such implants also raises the absolute numbers of implant-related infections. Thus, it is known that body-foreign materials are prone to bacterial adhesion and subsequent biofilm...

Université de Fribourg

Coordination polymer networks with s-block metal ions

Fromm, Katharina M.

In: Coordination Chemistry Reviews, 2008, vol. 252, no. 8-9, p. 856-885

Université de Fribourg

Silver nanoparticle engineering via oligovaline organogels

Mantion, Alexandre ; Guex, A. Geraldine ; Foelske, Annette ; Mirolo, Laurent ; Fromm, Katharina M. ; Painsi, Monika ; Taubert, Andreas

In: Soft Matter, 2008, vol. 4, no. 3, p. 606-617

L-Valine-based oligopeptides with the chemical structure Z–(L-Val)₃–OMe and Z–(L-Val)₂–L-Cys(S-Bzl)–OMe form stable organogels in butanol. Both peptides are efficient gelators, but Z–(L-Val)₂–L-Cys(S-Bzl)–OMe crystallizes more readily than Z–(L-Val)₃–OMe. The two peptides can form mixed fibers, which also gel butanol. The resulting organogels are very similar to...

Université de Fribourg

Analogy of the Coordination Chemistry of Alkaline Earth Metal and Lanthanide Ln²⁺ Ions: The Isostructural Zoo of Mixed Metal Cages [IM(OtBu)₄{Li(thf)}₄(OH)] (M=Ca, Sr, Ba, Eu), [MM′₆(OPh)₈(thf)₆] (M=Ca, Sr, Ba, Sm, Eu, M′=Li, Na), and their Derivatives with 1,2-Dimethoxyethane

Maudez, William ; Meuwly, Markus ; Fromm, Katharina M.

In: Chemistry - A European Journal, 2007, vol. 13, no. 29, p. 8302 - 8316

As previously shown, alkali and alkaline earth metal iodides in nonaqueous, aprotic solvents behave like transition metal halides, forming cis- and trans-dihalides with various neutral O-donor ligands. These compounds can be used as precursors for the synthesis of new mixed alkali/alkaline earth metal aggregates. We show here that Ln²⁺ ions form isostructural cluster compounds....