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For the first time, macroporous, elastic, three-dimensional hyaluronic acid cryogels were prepared with genipin as non-cytotoxic crosslinking agent. These cryogels are characterized by a lamellar porous structure with a homogeneous pore size of ~100 µm, shear elasticity of ~2 kPa and a swelling ratio of 2.5 in water. Additionally, multiple particle tracking based microrheology measurements reveal the formation of a heterogeneous network. This novel biomaterial owns great potential as non-cytotoxic alternative for application in drug delivery, as tissue engineering scaffold or wound healing substrate and can help reducing toxicity of artificial skin grafts or tissue equivalents. Keywords: Non-cytotoxic crosslinking, Genipin, Hyaluronic acid, 3D scaffold, Cryogelation

Although DNA nanotechnology has developed into a highly innovative and lively field of research at the interface between chemistry, materials science, and biotechnology, there is still a great need for methodological approaches for bridging the size regime of DNA nanostructures with that of micrometer‐ and millimeter‐sized units for practical applications. We report on novel hierarchically structured composite materials from silica nanoparticles and DNA polymers that can be obtained by self‐assembly through the clamped hybridization chain reaction. The nanocomposite materials can be assembled into thin layers within microfluidically generated water‐in‐oil droplets to produce mechanically stabilized hollow spheres with uniform size distributions at high throughput rates. The fact that cells can be encapsulated in these microcontainers suggests that our concept not only contributes to the further development of supramolecular bottom‐up manufacturing, but can also be exploited for applications in the life sciences.

35th European Photovoltaic Solar Energy Conference and Exhibition; 825-831, In December 2014, the publicly funded project "AdmMo: Advanced multi-crystalline Modules" initiated by Hanwha Q-Cells started with the partners Heraeus, Frintrup, Innolas-Solutions, Meyer Burger Germany, Wavelabs, Karlsruhe Institute of Technology, Bergakademie Freiberg, Fraunhofer CSP and Fraunhofer ISE. The content of the project, which ended on April 30th, 2018, is a comprehensive and consistent further development of PERC cell and module technology. The overall project objective is a reduction of the “Levelized Cost of Electricity” (LCoE) to < 6 € ct / kWh in relation to the southern German region. For this purpose, a substantial cost reduction with simultaneous increase in performance of the cells and modules as well as a service life of the modules extended to 30 years was aspired. Our conference paper gives an overview of the most important results. Among other things, Cz-PERC solar cells with efficiencies > 22 % and based on this a module of 120 half-cells with a power output of 318 watts is demonstrated.

We present a comprehensive micro- and macrorheological study of the effect of weak depletion attraction (Ψdep ≈ 1–10 kBT) on dense colloidal suspensions stabilized by short-range repulsive interactions. We used aqueous polymer dispersions as model system and demonstrated the unique capabilities of multiple particle tracking (MPT) to disclose structural changes in such technically important systems exhibiting many characteristic features of hard sphere systems. Below the hard sphere freezing point ϕc, viscosity increases monotonically with increasing Ψdep due to the transition from a fluid to a fluid/crystalline and finally to a gel state. Above ϕc, increasing attraction strength first results in a viscosity reduction corresponding to the formation of large, permeable crystals and then in a viscosity increase when a network of dense, small crystals forms. The fraction of the fluid and crystal phase, particle concentration in each phase as well as the modulus of the micro-crystals are obtained, the latter decreases with Ψdep. Above the colloidal glass transition strong heterogeneities and different local particle mobility in the repulsive and attractive arrested states are found. Particles are trapped in the cage of neighboring particles rather than in an attractive potential well. The intermediate ergodic state exhibits uniform tracer diffusivity.