The frequency-dependent shear modulus of aqueous wormlike micellar solutions cetylpyridinium chloride (CPyCl) and sodium salicylate (NaSal) has been measured over a broad frequency range from 10−2 to 106 rad/s using diffusing wave spectroscopy (DWS) based tracer microrheology as well mechanical techniques including rotational rheometry oscillatory squeeze flow. Good agreement between optical is found in the 10−1 105 (Willenbacher, N.; Oelschlaeger, C.; Schopferer, M.; Fischer, P.; Cardinaux,...

We have studied the effect of counterion binding efficiency on linear viscoelastic properties wormlike micelles formed from hexadecyltrimethylammonium bromide (CTAB) in presence different nonpenetrating inorganic salts: potassium (KBr), sodium nitrate (NaNO3), and chlorate (NaClO3). varied salt/surfactant ratio R at fixed surfactant concentration 350 mM. Results are compared to data for system cetylpyridinium chloride (CPyCl) penetrating salicylate (NaSal) (Oelschlaeger, C.; Schopferer, M.;...

Abstract Continuous flow biocatalysis is an emerging field of industrial biotechnology that uses enzymes immobilized in channels for the production value‐added chemicals. We describe construction self‐assembling all‐enzyme hydrogels are comprised two tetrameric enzymes. The stereoselective dehydrogenase LbADH and cofactor‐regenerating glucose 1‐dehydrogenase GDH were genetically fused with a SpyTag or SpyCatcher domain, respectively, to generate complementary homo‐tetrameric building blocks...

We characterize the linear viscoelastic shear properties of an aqueous wormlike micellar solution using diffusing wave spectroscopy (DWS) based tracer microrheology as well various mechanical techniques such rotational rheometry, oscillatory squeeze flow, and torsional resonance oscillation covering frequency range from ${10}^{\ensuremath{-}1}$ to ${10}^{6}\text{ }\text{ }\mathrm{rad}/\mathrm{s}$. Since DWS flow cover a sufficiently high range, persistence length micelles could be determined...

In this work, we present new insights related to a debate on the morphological structure of hydroxyethyl cellulose (HEC) molecules when dissolved in water, i.e., whether HEC adopts linear-flexible or rod-like fibrillar configuration. We have employed "seven" rheological techniques explore viscoelastic properties solutions at different time and length scales. This work demonstrates an excellent convergence between various over broad range frequencies concentrations, allowing us derive...

We have investigated the linear viscoelastic properties of high molecular weight hyaluronan in aqueous solution using an experimental approach combining mechanical rheometry and optical microrheology. The complex shear modulus has been measured over a broad frequency range from 10(-1) to 10(7) rad/s. Chain flexibility is characterized by persistence length lpand this parameter determined for first time entangled regime here data. At NaHA concentrations above entanglement concentration ce, lp...

Abstract Biomedical applications require substrata that allow for the grafting, colonization and control of eukaryotic cells. Currently available materials are often limited by insufficient possibilities integration biological functions means tuning mechanical properties. We report on tailorable nanocomposite in which silica nanoparticles interwoven with carbon nanotubes DNA polymerization. The modular, well controllable scalable synthesis yields whose composition can be gradually adjusted...

In this study, macroporous, elastic, three-dimensional scaffolds formed of hyaluronic acid mixed with ethylene glycol diglycidyl ether as a chemical cross-linker have been prepared by cryogelation for application in tissue engineering. These cryogels are characterized large interconnected pores size ∼50-300 μm and pore wall thickness ∼5-30 determined from confocal microscopy images. Variation pH, freezing temperature, polymerization time allows control shape well matrix thickness. structural...

All-enzyme hydrogels are efficient reagents for continuous flow biocatalysis.

We have investigated the uniaxial elongation behavior of six different wormlike micelle systems covering a broad range surfactant concentrations cs and salt/surfactant ratios R using capillary breakup elongational rheometry (CaBER). In fast-breaking limit (high R), filament lifetime tfil is controlled by equilibrium shear modulus G0 breakage time λbr obtained from small oscillatory according to tfil/G0∝λbr2/3 relaxation λe/λs≈1 are found. When reptation dominates cs, low R) λe/λs<1...

We developed a new data analysis strategy, the so-called micro-rheo-mapping technique, based on multiparticle tracking experiments to obtain an accurate and direct visualization of microstructure commercial acrylate thickeners Carbopol-type with high (Ultrez 10), intermediate (ETD 2020), low 2050) degree crosslinking. At polymer concentration, aggregates made several primary Carbopol particles are formed average diameter 43 ± 11, 56 14, 10 2.5 μm for Ultrez 10, ETD 2020, 2050, respectively....

Carrier-free enzyme immobilization techniques are an important development in the field of efficient and streamlined continuous synthetic processes using microreactors. Here, use monolithic, self-assembling all-enzyme hydrogels is expanded to phenolic acid decarboxylases. This provides access flow production p-hydroxystyrene from p-coumaric for more than 10 h with conversions ≥98% space time yields 57.7 g·(d·L)−1. Furthermore, modulation degree crosslinking resulted a defined variation...

Abstract Mechanical rheometry, specifically rotational squeeze flow, and capillary two microrheology methods, namely multiple-particle tracking (MPT) diffusing wave spectroscopy (DWS) have been used to get new insight into structural dynamical properties of alginate dissolved in solvents widely for bioprinting, deionized water, phosphate-buffered saline (PBS), Dulbecco Modified Eagle Medium (DMEM) cell media. Results demonstrate that rheological depend on the solvent quality at...

As mechanical properties of cell culture substrates matter, methods for characterization scaffolds on a relevant length scale are required. We used multiple particle tracking microrheology to close the gap between elasticity determined from bulk measurements and elastic sensed by cells. Structure macroporous, three-dimensional cryogel mixtures hyaluronic acid (HA) collagen (Coll) were characterized. Both one-component gels formed homogeneous networks, whereas hybrid heterogeneous in terms...

We show that fluorescence correlation spectroscopy (FCS) using a commercial spectrometer can be applied to passive microrheological (MR) experiments. The method probes the local rheological properties of materials on length scales focus dimension confocal microscope. For feasibility study, we performed measurements high molecular weight poly(ethylene oxide)-water solution allow direct comparison results previous studies diffusing wave spectroscopy, quasielastic light scattering, and particle...

Tracking errors due to particles moving in and out of the focal plane are a fundamental problem multiple particle tracking microrheology. Here, we present new approach treat these so that statistically significant number trajectories with reasonable length received, which is important for an unbiased analysis data from inhomogeneous fluids. Starting Crocker Grier's algorithm, identify displacements between subsequent images as artificial jumps; if this displacement deviates more than four...

Abstract Continuous flow biocatalysis is an emerging field of industrial biotechnology that uses enzymes immobilized in channels for the production value‐added chemicals. We describe construction self‐assembling all‐enzyme hydrogels are comprised two tetrameric enzymes. The stereoselective dehydrogenase LbADH and cofactor‐regenerating glucose 1‐dehydrogenase GDH were genetically fused with a SpyTag or SpyCatcher domain, respectively, to generate complementary homo‐tetrameric building blocks...

Abstract Although DNA nanotechnology has developed into a highly innovative and lively field of research at the interface between chemistry, materials science, biotechnology, there is still great need for methodological approaches bridging size regime nanostructures with that micrometer‐ millimeter‐sized units practical applications. We report on novel hierarchically structured composite from silica nanoparticles polymers can be obtained by self‐assembly through clamped hybridization chain...

Accurate quantification of polymerized DNA in rolling circle amplification (RCA)-based hydrogels is challenging due to the high viscosity these materials, however, it can be achieved with a photometric nucleotide depletion assay or qPCR. We show that content strongly depends on template sequence and correlates mechanical properties hydrogels.

Abstract Despite the critical role of hydrogels in material science and biotechnology, current methods for analyzing their formation lack real‐time monitoring require complex sample preparation instrumentation. In this work, an innovative methodology is introduced analysis enzymatically catalyzed hydrogelation. Electrochemical impedance spectroscopy (EIS) coupled with interdigitated electrodes (IDEs) to sense transduce gelation reaction model precursor carboxymethyl cellulose‐tyramine...

Abstract The advent of biomedical applications soft bioinspired materials has entailed an increasing demand for streamlined and expedient characterization methods meant both research quality control objectives. Here, a novel measurement system the biological hydrogels with volumes as low 75 µL was developed. is based on indentation platform equipped micrometer drive actuators that allow determination fracture points Young's moduli relatively stiff polymers, including agarose, well...

Abstract The microphase orientation/reorientation alignment kinetics behaviour of lamellar PS‐ b ‐PB diblock and ‐PB‐ ‐PS triblock copolymers under LAOS conditions is studied. By online monitoring the degree mechanical nonlinearity during orientation process, as determined via higher harmonics in FT rheology [i.e: I 3/1 ( t ), ϕ 3 )], investigation distribution by 2D‐SAXS, for different experimental shear was followed. For di‐ copolymers, into parallel possible strongly dependent on strain...