Christina’s paper on “cell death or survival instructed by supramolecular cohesion” highlighted by phys.org

syntheticpepSynthetic peptides use the force to influence cell survival

(Phys.org) —Peptide amphiphiles (PAs) are an emerging class of molecules that can be designed for novel therapies in advanced medicine. They are designed with structural regions that allow them to spontaneously assemble into large complex structures like nanofibers (fibers with diameters of approximately 10 nanometers). Researchers in this study investigated how positively charged PAs interact with cells when water-hating properties and hydrogen bonding (a force that holds the nanofibers together) are altered. Using the BioCARS beamline 14-BM-C at the U.S. Department of Energy Office of Science’s Advanced Photon Source (APS) to collect data, they evaluated forces within the biological assemblies.

Read more at: http://phys.org/news/2014-05-synthetic-peptides-cell-survival.html

Just add acid for stiffness

TUDelta News: Delft researchers have made hydrogels with tunable stiffness that seem promising for culturing stem cells and cleaning up oil slicks at sea. 

Whether it is for applications in biomedical industry, petrochemicals or cosmetics, you don’t want your hydrogel to be too slimy or too stiff. Dr. Rienk Eelkema, and colleagues from his Advanced Soft Matter group (AS faculty), have recently discovered a simple way to make gels at room temperature with tunable stiffness thereby solving a long-standing problem of adjusting the texture. They published an article about it earlier this month online in Nature Chemistry. Read more.

 

Gel voor biomedische toepassing supersnel te fabriceren

NWO News: Moleculaire hydrogels hebben enorm veel mogelijke toepassingen in gebieden zoals cel- en weefselkweek, de petrochemische industrie en cosmetica, maar de hiervoor belangrijke eigenschappen van de gel zijn moeilijk te sturen. NWO-onderzoeker Rienk Eelkema van de TU Delft ontwikkelde een techniek waarmee de gels met behulp van katalysatoren gemakkelijk en nauwkeurig bij kamertemperatuur gemaakt kunnen worden. Hij publiceert daarover in Nature Chemistry.

From NWO: Read more.

Tunable release platform highlighted in Chemistry & Industry

Chemistry and Industry Highlight: Delivery platform with post-production tunable release rate

Self-assembly of three molecular components results in a delivery platform, the release rate of which can be tuned after its production (J. Boekhoven, M. Koot , T. A. Wezendonk, R. Eelkema, J. H. van Esch; J. Am. Chem. Soc., 2012, 134, 12908) (Scheme 2). A fluorophore-conjugated gelator can be hydrolysed by an enzyme, resulting in the release of a fluorescent small molecule. To allow the release to be tunable, the enzyme is entrapped in liposomes and can be liberated by heating the system for a short period. Crucially, the heating time determines the amount of enzyme liberated; with that, the release rate can be tuned by the time of heating.

Read more

Tunable release rate platform highlighted by ChemistryViews

ChemistryViews Highlight: To develop a model delivery platform with a tunable release rate, Jan H. van Esch and colleagues, Delft University of Technology, The Netherlands, designed a system comprised of three major components: a hydrogelator, a proteolytic enzyme, and a phospholipid. The low-molecular-weight hydrogelator, based on a cyclohexane-tris-amide core, is covalently connected to the fluorogenic molecule 6-aminoquinoline (6-AQ) via an enzymatically hydrolyzable amide linker. Read More.

Seeding Sprinkles of Hope

TUDelta News: PhD student Job Boekhoven won a NWO Rubicon grant and will soon be heading to Chicago to develop injectable microspheres to repair brain damage resulting from strokes.

Job Boekhoven, who conducted his PhD research at Professor Jan van Esch’s lab (Applied Sciences), specialised in making self-assembling molecules, which often have a hydrophilic (water-loving) and a hydrophobic (oil-loving) side. In watery surroundings, such soap-like molecules tend to cling together and form vesicles, fibrils, fibers or sheets – all depending on the circumstances (concentrations for one).
For his first postdoc research, Boekhoven was searching for something that would be partly familiar but sufficiently new at the same time. He found what he was looking for at the laboratories of Professor Samuel Stupp at Northwestern University in Chicago (US).

My postdoctoral work explained in the TUDelta.

Dissipative self-assembly highlighted

Nature Chemistry Highlight: An alkylating agent is constantly consumed to fuel the formation of a self-assembled gel that exists far from equilibrium.

A vast array of different structures can be formed by exploiting reversible, multiple weak intermolecular interactions. The structures that are formed are, for the most part, stable at equilibrium. Inspiration for research into such self-assembled structures often comes from natural systems, but in reality these often exist far from equilibrium and require the constant input of chemical energy to remain assembled. Now, Jan van Esch and co-workers from Delft University of Technology have developed1 a gel- forming system that consumes a ‘chemical fuel’ to mimic this behaviour.

Our work on Dissipative Self-Assembly was reviewed as “hot paper” and highlighted in Nature Chemistry.