Soft Matter Blog

Read for free until 30 September>>>

Amphiphilic triblock copolymers: A new study demonstrates that the length of a polyethylene glycol (PEG) spacer has a crucial impact on the association behaviour of temperature sensitive triblock copolymers at elevated temperatures. Findings show that a short PEG length promotes formation of interchain complexes at high temperatures. Atoosa Maleki, Kaizheng Zhu, Ramón Pamies, Ricardo Rodríguez Schmidt, Anna-Lena Kjøniksen, Göran Karlsson, José G. Hernández Cifre, José García de la Torre and Bo Nyström, Soft Matter, 2011, DOI: 10.1039/C1SM05679D

Yield stress fluids: Stress-induced fluidization of a simple yield stress fluid, namely a carbopol microgel, is addressed through extensive rheological measurements coupled to simultaneous temporally and spatially resolved velocimetry. A clear link between the transient regime of the fluidization process and the steady-state rheology is presented for the first time. Thibaut Divoux, Catherine Barentin and Sébastien Manneville, Soft Matter, 2011, DOI: 10.1039/C1SM05607G

Lipid rafts: Ligand-induced transbilayer coupling of rafts is simulated in this Hot Article. Using coarse grained molecular dynamics (CGMD) simulations the authors show that raft registration arises spontaneously in bilayers with a calcium- or ligand-crosslinked ordered phase segregating from a liquid disordered phase. Diego A. Pantano, Preston B. Moore, Michael L. Klein and Dennis E. Discher, Soft Matter, 2011, DOI: 10.1039/C1SM05490B

Read free until 23 September>>>

Antimicrobial and antiviral hydrogels: This brief review provides some illustrative examples of different types of antimicrobial (antibacterial/antifungal) and antiviral hydrogels. The triggered response of the  hydrogels is discussed and a focus is placed on formulation principles, and on how the physicochemical properties of such hydrogels influence their antimicrobial/antiviral action. Martin Malmsten, Soft Matter, 2011, DOI: 10.1039/C1SM05809F

Thermal liquid crystal phases: An interaction assisted approach for realization of biaxiality in smectic A phases is demonstrated in addition to the effectiveness of perfluoroarene-arene and C-H/F interactions as the intermolecular interactions. The slow rotation of the molecules showed unique phenomena such as no clear odd–even effect in their clearing and melting points. Keiki Kishikawa, Takahiro Inoue, Yoshiyuki Sasaki, Sumihiro Aikyo, Masahiro Takahashi and Shigeo Kohmoto, Soft Matter, 2011, 7, 7532-7538, DOI: 10.1039/C1SM05887H

Stimuli-responsive hydrogels: Researchers have functionalised poly(N-isopropylacrylamide) gel with spirobenzopyrans and evaluated the effects of spontaneous ring-opening rates of the photo-chromic molecules on the light-responsive volume change of the subsequent gels. Rates of reswelling from the light-induced shrunken state of the spirobenzopyran-functionalized gels increased with increasing ring-opening rates of spirobenzopyrans in the gels. Taku Satoh, Kimio Sumaru, Toshiyuki Takagi and Toshiyuki Kanamori, Soft Matter, 2011, DOI: 10.1039/C1SM05797A

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Review article on ‘The physics of tissue patterning and extracellular matrix organisation: how cells join forces’.  The authors discuss how cells interact with other cells and with substrates to form complex tissues and organs. Important examples are the patterning of growth and differentiation within tissues and the long-range organisation of the extracellular matrix. P. Kollmannsberger, C. M. Bidan, J. W. C. Dunlop and P. Fratzl, Soft Matter, 2011, DOI: 10.1039/C1SM05588G

Self-organisation of dendrimers is extensively modeled through molecular dynamics simulations of a coarse grained dendron model to show how the thermodynamic conditions play a decisive role on its self-organization. A global phase diagram for dendrons which shows the relation between columnar and supramolecular sphere phases was also realised. Andrew J. Crane and Erich A. Müller, Soft Matter, 2011, 7, 7465-7476, DOI: 10.1039/C1SM05599B

An electrorheological (ER) effect in a single phase ER suspension in microgravity is reported for the first time. Potential applications of single-phase ER fluids may be found in outer-space stations with micro-gravity environment, serving as a tunable friction-generating material. Guoqing Zhao, Shuyu Chen, Weijia Wen, Fumiaki Miyamaru, Mitsuo W. Takeda, Jianding Yu and Ping Sheng, Soft Matter, 2011, 7, 7198-7200, DOI: 10.1039/C1SM05736G

Read these Hot Articles for free until 8 Sept >>>

Liquid Marbles are stabilised on the surface of an acidic liquid due to hydrophobic components. However, once the pH reaches 5.5 the stabilising chains become to hydrophilic and the sphere collapses. The organic polymer particles were made-up of polyacid-stabilised polystyrene latex. Damien Dupin, Kate L. Thompson and Steven P. Armes, Soft Matter, 2011, 7, 6797-6800,DOI: 10.1039/C1SM05889D

‘Liquid marble’ deposited onto (a) a glass slide and (b) the surface of liquid water in a Petri dish.

Partially fluorinated amphiphiles and their interaction with biomembrane lipids in Langmuir monolayers is studied in this Hot Article. This provides fundamental insights into the molecular function of biomembrane components and support for the biomedical use of fluorinated materials. Shorter perfluoroalkyl chains may have more potential for clinical use than higher fluorinated chains. Hiromichi Nakahara, Marie Pierre Krafft, Akira Shibata and Osamu Shibata, Soft Matter, 2011, 7, 7325-7333, DOI: 10.1039/C1SM05647F

Cross-slot extensional flow oscillatory rheometry, an opto-microfluidic technique, is used to quantify the response of elastic fluids to extensional flows. This understanding is necessary for optimising fluid composition for technological applications such as ink-jet printing. Elastic fluids are complex fluids which respond to applied stress with a combination of solid-like elasticity and liquid-like ability to flow. Simon J. Haward, Vivek Sharma and Jeffrey A. Odell, Soft Matter, 2011, DOI: 10.1039/C1SM05493G

Read these Hot Articles for free until 31 August>>>

Layer-by-layer (LbL) assemblies in nanoporous templates and their benefits for synthesising complex and functional nanotubular structures are described in this Review. 1D Nanostructures fabricated by the LbL nanotemplating strategy have applications in various technological areas, and are part of an emerging area of “soft nanotechnology”. Omar Azzaroni and K. H. Aaron Lau, Soft Matter, 2011, DOI: 10.1039/C1SM05561E.

Gelation of semiflexible polyelectrolytes by multivalent counterions: Filamentous polyelectrolyte viruses have been used to study liquid crystal phase transitions and counterion-mediated condensation into bundles. Longer filamentous phage Pf1 was found to form viscoelastic gels at concentrations well below its theoretical isotropic–nematic transition in solutions containing multivalent counterions. Elisabeth M. Huisman, Qi Wen, Yu-Hsiu Wang, Katrina Cruz, Guntars Kitenbergs, Kaspars Ērglis, Andris Zeltinš, Andrejs Cēbers and Paul A. Janmey, Soft Matter, 2011, DOI: 10.1039/C1SM05553D.

Organic thin film transistors: The reason behind improved performance of organic thin film transistor devices with 6,13-(triisopropylsilylethynyl) pentacene (TIPS-pentacene) is investigated in this Hot Article. Aggregation and cluster formation of TIPS-pentacene was observed in solution well before the solubility limit. Marie-Beatrice Madec, Sean Butterworth, Pablo Taboada, Richard Heenan, Mark Geoghegan and Stephen G. Yeates, Soft Matter, 2011, 7, 7065-7070, DOI: 10.1039/C1SM05842H.

 Read these Hot Articles for free until 31 August >>>

Wrinkling of materials can generate periodic nano or microstructures that are crucial for technological applications. Here, the phenomena is studied in ultra thin layers where Van der Waals interactions determine the morphologies. Findings indicate that wrinkling might not be the best way to investigate chain dynamics in these systems… Hugues Vandeparre, Simon Desbief, Roberto Lazzaroni, Cyprien Gay and Pascal Damman, Soft Matter, 2011, 7, 6878-6882, DOI: 10.1039/C1SM05411B

Holograms of colloidal spheres  were recorded with holographic video microscopy and analyzed with light scattering theory. Individual spheres’ sizes and refractive indexes were measured with part-per-thousand resolution, which was used to estimate each sphere’s porosity. Characterisation of single colloidal spheres is important for applications such as medical diagnostics and photonics. Fook Chiong Cheong, Ke Xiao, David J. Pine and David G. Grier, Soft Matter, 2011, 7, 6816-6819, DOI: 10.1039/C1SM05577A

Droplet-induced budding in biological membranes is when a liquid drop on the surface of the membrane transforms from being partially wrapped to completely wrapped (see below). This cellular process is important for endocytosis (for communication between organelles) and viral replication. Here, a novel budding mechanism where the driving force is the interfacial tensions between the aqueous phases is investigated. Halim Kusumaatmaja and Reinhard Lipowsky, Soft Matter, 2011, 7, 6914-6919, DOI: 10.1039/C1SM05499F