%0 journal article %@ 0010-938X %A Song, C., Wang, C., Mercier, D., Vaghenfinazari, B., Seyeux, A., Snihirova, D., Wieland, F.D.C., Marcus, P., Zheludkevich, M.L., Lamaka, S.V. %D 2024 %J Corrosion Science %P 111867 %R doi:10.1016/j.corsci.2024.111867 %T Corrosion inhibition mechanism of 2,6-pyridinedicarboxylate depending on magnesium surface treatment %U https://doi.org/10.1016/j.corsci.2024.111867 %X 2,6-pyridinedicarboxylate (2,6-PDC) was studied as corrosion inhibitor for pure magnesium. The surface was prepared either by polishing or polishing followed by treatment with 1 M NaOH solution. The results show that 2,6-PDC promotes the formation of a denser protective oxide/hydroxide layer poor in PDC. The mechanism proposed includes forming weak PDC-Mg complexes that lower the free Mg2+ concentration available for the formation of Mg(OH)2. This leads to growth of smaller Mg(OH)2 platelets that are more densely packed and hence form a more protective layer. The highest inhibition efficiency of 2,6-PDC was achieved for samples with surface hydroxylated by NaOH treatment. %0 journal article %@ 2468-0230 %A Yeshmanova, G., Blawert, C., Serdechnova, M., Wieland, F.D.C., Starykevich, M., Gazenbiller, E., Höche, D., Smagulov, D., Zheludkevich, M.L. %D 2024 %J Surfaces and Interfaces %P 103797 %R doi:10.1016/j.surfin.2023.103797 %T Effect of electrolyte composition on the formation of PEO coatings on AA2024 aluminium alloy %U https://doi.org/10.1016/j.surfin.2023.103797 %X Since the electrolyte composition plays a crucial role in the plasma electrolytic oxidation (PEO) coating formation process, a systematic and in-depth study was proposed to identify an electrolyte composition for fast PEO coating growth on AA2024 alloy. Different concentration ratios of mixed alkaline electrolytes (hydroxide, silicate and phosphate) were investigated. PEO process was conducted at low constant current density of 50 mA/cm2, which is intended for lowering the energy consumption. Results demonstrated that the breakdown voltage of PEO coatings is directly proportional to the logarithm of electrolyte resistivity. The coating growth mechanism showed two main directions. The thickening of the coating mainly depends on the rapid deposition of electrolyte compounds in Si-based electrolyte, and the coating growth occurs mainly towards the electrolyte/coating interface. Contrary, in OH-, and P-based electrolytes, the inward coating growth was dominating mainly by substrate oxidation. A variety of phases as a function of different electrolyte compositions and final voltages were observed. With high final voltages (over 470 V) for coatings produced in mixed electrolytes with low concentrations of hydroxide, silicate or phosphate (2 and 6 g/L), γ-Al2O3 crystalline phase predominates in the PEO layer composition. However, only a low efficiency of coating growth can be reached. In the electrolytes with high silicate concentrations accompanied by an increase of phosphate concentration, the final voltage is around 455 V and the coating composition is dominated by an amorphous phase in combination with crystalline mullite and γ-Al2O3. High silicate-phosphate contents (18–24 g/L) in mixed electrolytes with low final voltages of about 360 V results in a fully amorphous PEO layer and significantly increases coating thickness. A combination of low content of hydroxide, high silicate with increasing content of phosphate in mixed electrolyte increases the coating thickness, and improves the density and uniformity of the overall PEO layers. %0 journal article %@ 0010-938X %A Vaghefinazari, B., Lamaka, S.V., Gazenbiller, E., Yasakau, K., Blawert, C., Serdechnova, M., Scharnagl, N., Wieland, D.C.F., Zheludkevich, M.L. %D 2024 %J Corrosion Science %P 111651 %R doi:10.1016/j.corsci.2023.111651 %T Corrosion inhibition of decylphosphonate on bare and PEO-coated Mg alloy %U https://doi.org/10.1016/j.corsci.2023.111651 %X PEO coatings, aside from their reasonable corrosion protection, also feature a porous microstructure that can serve as a repository for corrosion inhibitors. This study presents and investigates the high corrosion inhibition effect of sodium salt of decylphosphonate (DP) when incorporated into PEO coating on a magnesium substrate. The interaction of DP with both bare and PEO-coated magnesium substrates was studied to understand its corrosion inhibition mechanism. Additionally, a strategy to enhance the active anti-corrosion ability of the DP-containing system was suggested and examined. The findings provide new insights into the potential of surfactants as corrosion inhibitors for magnesium alloys. %0 journal article %@ 1226-086X %A Kasneryk, V., Wu, T., Rohr, H., Serdechnova, M., Mojsilovi , K., Wieland, F.D.C., Davydok, A., Gazenbiller, E., Vasili , R., Blawert, C., Stock, N., Zheludkevich, M.L. %D 2024 %J Journal of Industrial and Engineering Chemistry %P 119538 %R doi:10.1016/j.jiec.2023.11.033 %T Controllable recrystallization of ZnO/ZnAl2O4 based PEO into ZIF-8 as a route for the formation of multifunctional coatings %U https://doi.org/10.1016/j.jiec.2023.11.033 %X Nowadays, plasma electrolytic oxidation (PEO) has become widespread as an effective method for preparation of multifunctional coatings. However, the PEO coatings have numerous pores. On the one hand, their presence restricts their broad application; on the other hand, they represent an excellent platform for post-sealing allowing creating coatings with peculiar properties. In the current work, the possibility of controllable recrystallization of ZnO/ZnAl2O4 based PEO preformed on Zn Z1 alloy into ZIF-8@PEO composite coating was demonstrated for the first time. It was found that the corrosion protection, photocatalytic and photoluminescence properties of the final coatings can be modified by varying the conditions of the post-modification process, which include the amount of the organic linker (2-methylimidazole) and treatment time. This study opens an innovative approach for the formation of multifunctional coatings. %0 journal article %@ 2452-199X %A Sefa, S., Espiritu, J., Ćwieka, H., Greving, I., Flenner, S., Will, O., Beuer, S., Wieland, D.C.F., Willumeit-Römer, R., Zeller-Plumhoff, B. %D 2023 %J Bioactive Materials %P 154-168 %R doi:10.1016/j.bioactmat.2023.07.017 %T Multiscale morphological analysis of bone microarchitecture around Mg-10Gd implants %U https://doi.org/10.1016/j.bioactmat.2023.07.017 %X The utilization of biodegradable magnesium (Mg)-based implants for restoration of bone function following trauma represents a transformative approach in orthopaedic application. One such alloy, magnesium-10 weight percent gadolinium (Mg-10Gd), has been specifically developed to address the rapid degradation of Mg while enhancing its mechanical properties to promote bone healing. Previous studies have demonstrated that Mg-10Gd exhibits favorable osseointegration; however, it exhibits distinct ultrastructural adaptation in comparison to conventional implants like titanium (Ti). A crucial aspect that remains unexplored is the impact of Mg-10Gd degradation on the bone microarchitecture. To address this, we employed hierarchical three-dimensional imaging using synchrotron radiation in conjunction with image-based finite element modelling. By using the methods outlined, the vascular porosity, lacunar porosity and the lacunar-canaliculi network (LCN) morphology of bone around Mg-10Gd in comparison to Ti in a rat model from 4 weeks to 20 weeks post-implantation was investigated. Our investigation revealed that within our observation period, the degradation of Mg-10Gd implants was associated with significantly lower (p < 0.05) lacunar density in the surrounding bone, compared to Ti. Remarkably, the LCN morphology and the fluid flow analysis did not significantly differ for both implant types. In summary, a more pronounced lower lacunae distribution rather than their morphological changes was detected in the surrounding bone upon the degradation of Mg-10Gd implants. This implies potential disparities in bone remodelling rates when compared to Ti implants. Our findings shed light on the intricate relationship between Mg-10Gd degradation and bone microarchitecture, contributing to a deeper understanding of the implications for successful osseointegration. %0 journal article %@ 2452-199X %A Bruns, S., Krüger, D., Galli, S., Wieland, D.C.F., Hammel, J.U., Beckmann, F., Wennerberg, A., Willumeit-Römer, R., Zeller-Plumhoff, B., Moosmann, J. %D 2023 %J Bioactive Materials %P 155-166 %R doi:10.1016/j.bioactmat.2023.05.006 %T On the material dependency of peri-implant morphology and stability in healing bone %U https://doi.org/10.1016/j.bioactmat.2023.05.006 %X The microstructural architecture of remodeled bone in the peri-implant region of screw implants plays a vital role in the distribution of strain energy and implant stability. We present a study in which screw implants made from titanium, polyetheretherketone and biodegradable magnesium-gadolinium alloys were implanted into rat tibia and subjected to a push-out test four, eight and twelve weeks after implantation. Screws were 4 mm in length and with an M2 thread. The loading experiment was accompanied by simultaneous three-dimensional imaging using synchrotron-radiation microcomputed tomography at 5 μm resolution. Bone deformation and strains were tracked by applying optical flow-based digital volume correlation to the recorded image sequences. Implant stabilities measured for screws of biodegradable alloys were comparable to pins whereas non-degradable biomaterials experienced additional mechanical stabilization. Peri-implant bone morphology and strain transfer from the loaded implant site depended heavily on the biomaterial utilized. Titanium implants stimulated rapid callus formation displaying a consistent monomodal strain profile whereas the bone volume fraction in the vicinity of magnesium-gadolinium alloys exhibited a minimum close to the interface of the implant and less ordered strain transfer. Correlations in our data suggest that implant stability benefits from disparate bone morphological properties depending on the biomaterial utilized. This leaves the choice of biomaterial as situational depending on local tissue properties. %0 journal article %@ 0257-8972 %A Kasneryk, V., Poschmann, M.P.M., Serdechnova, M., Dovzhenko, G., Wieland, D.C.F., Karlova, P., Naacke, T., Starykevich, M., Blawert, C., Stock, N., Zheludkevich, M.L. %D 2022 %J Surface and Coatings Technology %P 128733 %R doi:10.1016/j.surfcoat.2022.128733 %T Formation and structure of ZIF-8@PEO coating on the surface of zinc %U https://doi.org/10.1016/j.surfcoat.2022.128733 %X Recently, plasma electrolytic oxidation (PEO) found broad application as a multi-purpose process to create effective corrosion and wear resistant coatings on various metallic substrates. The exceptional properties of metal organic frameworks (MOFs) put them also in focus as perspective materials for corrosion protection. In this work, the formation of a novel ZIF-8@PEO coating is reported for the first time. It was synthesized by controllable recrystallization of a PEO layer formed on zinc alloy Z1 into ZIF-8 in the presence of 2-methylimidazole organic linkers. The multi-stage mechanism of PEO to ZIF-8 rearrangement is proposed. Cross section, glow discharge optical emission spectroscopy and nano-focused synchrotron X-ray diffraction demonstrated that varying of synthesis parameters, the ZIF-8@PEO coating with different distribution of ZIF-8 through PEO layer can be prepared. Based on the results of laser scanning microscopy, the surface smoothing was observed with increasing the degree of the PEO-to-ZIF-8 rearrangement. Containing two components, the novel ZIF-8@PEO coating is expected to combine admirable physical-chemical properties of both PEO and ZIF-8. Such a feature can open the way for its potential application not only for corrosion protection, but also for photo- and heterogeneous catalysis. %0 journal article %@ 0010-938X %A Vaghefinazari, B., Lamaka, S.V., Blawert, C., Serdechnova, M., Scharnagl, N., Karlova, P., Wieland, D.C.F., Zheludkevich, M.L. %D 2022 %J Corrosion Science %P 110344 %R doi:10.1016/j.corsci.2022.110344 %T Exploring the corrosion inhibition mechanism of 8-hydroxyquinoline for a PEO-coated magnesium alloy %U https://doi.org/10.1016/j.corsci.2022.110344 %X In this study, the corrosion inhibition effect of 8-hydroxyquinoline (8HQ) on a PEO-coated AZ21 magnesium alloy is explored. The interaction of 8HQ molecules with both bare AZ21 and PEO layer was thoroughly scrutinized during the exposure to a corrosive NaCl electrolyte using different characterization methods, including EIS, SEM, Raman spectroscopy, and XRD. The corrosion inhibition mechanism stems from the extensive precipitation of the insoluble complex between 8HQ molecules and Mg2+ on top of the PEO layer, which leads to subsequently inhibition-enhancing phenomena, including modification of the corrosion products and re-precipitation of the PEO amorphous phase. %0 journal article %@ 0169-4332 %A Ignjatović, S., Blawert, C., Serdechnova, M., Karpushenkov, S., Damjanović, M., Karlova, P., Wieland, D.C.F., Starykevich, M., Stojanović, S., Damjanović-Vasilić, L., Zheludkevich, M.L. %D 2021 %J Applied Surface Science %P 148875 %R doi:10.1016/j.apsusc.2020.148875 %T Formation of multi-functional TiO2 surfaces on AA2024 alloy using plasma electrolytic oxidation %U https://doi.org/10.1016/j.apsusc.2020.148875 %X It was found that the coating thickness and surface morphology are strongly dependent on the PEO processing time. However, the phase composition is not much affected by the treatment time and the main coating phase is rutile with a smaller amount of anatase. Adding additional anatase in the form of particles increases the amount of anatase in the coatings. The additional particle addition has only minor effect on the corrosion resistance, but reduces the wear resistance remarkably. Interestingly, the addition of anatase particles and the PEO treatment time are not effective in increasing the photocatalytic activities of the samples. %0 journal article %@ 0169-4332 %A Bouali, A.C., Iuzviuk, M.H., Serdechnova, M., Yasakau, K.A., Wieland, D.C.F., Dovzhenko, G., Maltanava, H., Zobkalo, I.A., Ferreira, M.G.S., Zheludkevich, M.L. %D 2020 %J Applied Surface Science %P 144027 %R doi:10.1016/j.apsusc.2019.144027 %T Zn-Al LDH growth on AA2024 and zinc and their intercalation with chloride: Comparison of crystal structure and kinetics %U https://doi.org/10.1016/j.apsusc.2019.144027 %X The current study revealed noticeable changes on the positioning of the interlayer atoms for the ZnAl-LDH-Cl on zinc in comparison with the ones on AA2024 substrate. %0 journal article %@ 1742-7061 %A Zeller-Plumhoff, B., Malich, C., Krueger, D., Campbell, G., Wiese, B., Galli, S., Wennerberg, A., Willumeit-Römer, R., Wieland, D.C.F. %D 2020 %J Acta Biomaterialia %P 637-645 %R doi:10.1016/j.actbio.2019.11.030 %T Analysis of the bone ultrastructure around biodegradable Mg–xGd implants using small angle X-ray scattering and X-ray diffraction %U https://doi.org/10.1016/j.actbio.2019.11.030 %X Magnesium alloys are increasingly researched as temporary biodegradable metal implants in bone applications due to their mechanical properties which are more similar to bone than conventional implant metals and the fact that Magnesium occurs naturally within the body. However, the degradation processes in vivo and in particular the interaction of the bone with the degrading material need to be further investigated. In this study we are presenting the first quantitative comparison of the bone ultrastructure formed at the interface of biodegradable Mg–5Gd and Mg–10Gd implants and titanium and PEEK implants after 4, 8 and 12 weeks healing time using two-dimensional small angle X-ray scattering and X-ray diffraction. Differences in mineralization, orientation and thickness of the hydroxyapatite are assessed. We find statistically significant (p < 0.05) differences for the lattice spacing of the (310)-reflex of hydroxyapatite between titanium and Mg–xGd materials, as well as for the (310) crystal size between titanium and Mg–5Gd, indicating a possible deposition of Mg within the bone matrix. The (310) lattice spacing and crystallite size further differ significantly between implant degradation layer and surrounding bone (p < 0.001 for Mg–10Gd), suggesting apatite formation with significant amounts of Gd and Mg within the degradation layer. %0 journal article %@ 2040-3364 %A Sankhala, K., Wieland, D.C.F., Koll, J., Radjabian, M., Abetz, C., Abetz, V. %D 2019 %J Nanoscale %N 16 %P 7634-7647 %R doi:10.1039/C8NR06892E %T Self-assembly of block copolymers during hollow fiber spinning: an in situ small-angle X-ray scattering study %U https://doi.org/10.1039/C8NR06892E 16 %X We investigated the self-assembly of block copolymers during hollow fiber membrane (HFM) fabrication by conducting in situ small angle X-ray scattering (SAXS) and ex situ scanning electron microscopy (SEM) studies. SAXS enables us to follow the structural rearrangements after extrusion at different distances from the spinning nozzle. The kinetics of the spinning process is examined as a function of the composition of block copolymer solutions and the spinning parameters. We studied the influence of the extrusion rate on the block copolymer microdomains and their self-assembly in weakly segregated and ordered solutions. The addition of magnesium acetate (MgAc2) leads to the ordering of micelles in the block copolymer solution already at lower polymer concentrations and shows an increased number of micelles with larger domain spacing as compared to the pristine solution. The SAXS data show the effect of shear within the spinneret on the self-assembly of block copolymers and the kinetics of phase separation after extrusion. It is observed that the ordering of micelles in solutions is decreased as indicated by the loss of crystallinity while high extrusion rates orient the structures perpendicular to the fiber direction. The structural features obtained from in situ SAXS experiments are correlated to the structure in the block copolymer solutions in the absence of shear and the morphologies in flat sheet and HF membranes obtained by ex situ SEM. This allows a systematic and comparative study of the effects varying the microdomain ordering within different block copolymer solutions and the formed membrane structures. %0 conference lecture %@ %A Sankhala, K., Koll, J., Wieland, D.C.F., Radjabian, M., Abetz, C., Abetz, V. %D 2019 %J Dead Sea Water 2019 Workshop, Nanomaterials at the water-energy nexus %T Self-Assembly of Block Copolymers in Isoporous Hollow Fiber Membranes %U %X %0 conference poster %@ %A Waldner, A., Bergmann, C., Wieland, D.C.F, Emmert, S., Nebe, B. %D 2019 %J 6th International Workshop on Plasma for Cancer Treatment, IWPCT 2019 %T Effect of Cold Atmospheric Pressure Plasma Treated Medium on Dermal Cancer Cells in Vitro %U %X %0 journal article %@ 0370-1972 %A Kalanda, N., Haramus, V.M., Avdeev, M., Zheludkevich, M.L., Yarmolich, M., Serdechnova, M., Wieland, D.C.F., Petrov, A., Zhaludkevich, A., Sobolev, N. %D 2019 %J Physica Status Solidi B %N 5 %P 1800428 %R doi:10.1002/pssb.201800428 %T Small‐Angle Neutron Scattering and Magnetically Heterogeneous State in Sr2FeMoO6–δ %U https://doi.org/10.1002/pssb.201800428 5 %X Single‐phase strontium ferromolybdate (Sr2FeMoO6–δ) samples with different degrees of the superstructural ordering of the Fe/Mo cations (P) are obtained from partially reduced SrFeO3–х, SrMoO4 precursors by the solid‐state technology. The study of the temperature dependences of the magnetization measured in the field‐cooling and zero‐field‐cooling modes indicated an inhomogeneous magnetic state of the samples. The presence of magnetic regions of different nature has also been revealed by the small‐angle neutron scattering. For the Sr2FeMoO6–δ samples with different P values and for all values of the magnetic field induction up to 1.5 T and of the scattering vector in the interval 0.1 > q > 0.002 Å−1, the analytical dependence I ∼ q–α obeys the Porod law (α ≈ 4), which corresponds to an object with a smooth and well‐marked surface and polydisperse grain size. Deviations from the Porod law in the q > 0.1 Å−1 region and a weakening of the neutron scattering in applied magnetic fields may be ascribed to magnetic inhomogeneities with diameters D < 6 nm, which are partially destroyed/oriented by magnetic fields В ≥ 1.5 T. It is established that the magnetic homogeneity of the Sr2FeMoO6–δ compound is enhanced with increasing superstructural ordering of the Fe/Mo cations. %0 conference poster %@ %A Sankhala, K., Wieland, D.C.F., Koll, J., Radjabian, M., Abetz, C., Abetz, V. %D 2019 %J 28th Annual North American Membrane Society Meeting, NAMS 2019 %T Structure Formation in Isoporous Hollow Fiber Membranes: An In Situ SAXS study %U %X %0 conference lecture %@ %A Sankhala, K., Koll, J., Wieland, D.C.F., Radjabian, M., Abetz, C., Abetz, V. %D 2019 %J 28th Annual North American Membrane Society Meeting, NAMS 2019 %T Fabrication of Inside-Out Isoporous Hollow Fiber Membranes via Spinning and Coating Methods %U %X %0 conference poster %@ %A Zeller-Plumhoff, B., Malich, C., Krueger, D., Campbell, G., Galli, S., Wennerberg, A., Willumeit-Roemer, R., Wieland, D.C.F. %D 2019 %J 11th Symposium on Biodegradable Metals, Biometal 2019 %T Assessing the interface ultrastructure of bone around biodegradable implants %U %X %0 conference poster %@ %A Zeller-Plumhoff, B., Wieland, D.C.F., Malich, C., Krueger, D., Campbell, G., Moosmann, J., Galli, S., Wennerberg, A., Willumeit-Roemer, R. %D 2019 %J 6th International Symposium Interface Biology of Implants %T Assessing the interface ultrastructure of bone around biodegradable implants %U %X %0 conference object %@ %A Zeller-Plumhoff, B., Wieland, D.C.F., Malich, C., Krueger, D., Campbell, G., Moosmann, J., Galli, S., Wennerberg, A., Willumeit-Roemer, R. %D 2019 %J Book of Abstracts, 6th International Symposium Interface Biology of Implants %P 86-P %T Assessing the interface ultrastructure of bone around biodegradable implants %U %X %0 conference object %@ %A Zeller-Plumhoff, B., Malich, C., Krueger, D., Campbell, G., Galli, S., Wennerberg, A., Willumeit-Roemer, R., Wieland, D.C.F. %D 2019 %J Abstract Book, 11th Symposium on Biodegradable Metals, Biometal 2019 %P InVit-10 %T Assessing the interface ultrastructure of bone around biodegradable implants %U %X %0 conference lecture %@ %A Moosmann, J., Wieland, D.C.F., Zeller-Plumhoff, B., Galli, S., Krueger, D., Ershov, A., Lautner, S., Sartori, J., Dean, M., Koehring, S., Burmester, H., Dose, T., Peruzzi, N., Wennerberg, A., Willumeit-Roemer, R., Wilde, F., Heuser, P., Hammel, J.U., Beckmann, F. %D 2019 %J Developments in X-Ray Tomography XII, SPIE Optics and Photonics Conference 2019 %T A load frame for in situ tomography at PETRA III %U %X %0 conference paper %@ %A Moosmann, J., Wieland, D.C.F., Zeller-Plumhoff, B., Galli, S., Krueger, D., Ershov, A., Lautner, S., Sartori, J., Dean, M., Koehring, S., Burmester, H., Dose, T., Peruzzi, N., Wennerberg, A., Willumeit-Roemer, R., Wilde, F., Heuser, P., Hammel, J.U., Beckmann, F. %D 2019 %J Proceedings of SPIE, Developments in X-Ray Tomography XII %P 1111318 %T A load frame for in situ tomography at PETRA III %U %X %0 conference poster %@ %A Bockelmann, N., Krueger, D., Wieland, D,C.F., Zeller-Plumhoff, B., Peruzzi, N., Galli, S., Willumeit-Roemer, R., Wilde, F., Beckmann, F., Hammel, J.U., Moosmann, J., Heinrich, M.P. %D 2019 %J International Conference on Medical Imaging with Deep Learning, MIDL 2019 %T Sparse Annotations with Random Walks for U-Net Segmentation of Biodegradable Bone Implants in Synchrotron Microtomograms %U %X %0 journal article %@ 1744-683X %A Zander, T., Wieland, D.C.F., Raj, A., Salmen, P., Dogan, S., Dedinaite, A., Haramus, V.M., Schreyer, A., Claesson, P.M., Willumeit-Römer, R. %D 2019 %J Soft Matter %N 36 %P 7295-7304 %R doi:10.1039/C9SM01066A %T Influence of high hydrostatic pressure on solid supported DPPC bilayers with hyaluronan in the presence of Ca2+ ions %U https://doi.org/10.1039/C9SM01066A 36 %X The molecular mechanisms responsible for outstanding lubrication of natural systems, like articular joints, have been the focus of scientific research for several decades. One essential aspect is the lubrication under pressure, where it is important to understand how the lubricating entities adapt under dynamic working conditions in order to fulfill their function. We made a structural investigation of a model system consisting of two of the molecules present at the cartilage interface, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine and hyaluronan, at high hydrostatic pressure. Phospholipid layers are found at the cartilage surfaces and are able to considerably reduce friction. Their behavior under load and varied solution conditions is important as pressures of 180 bar are encountered during daily life activities. We focus on how divalent ions, like Ca2+, affect the interaction between DPPC and hyaluronan, as other investigations have indicated that calcium ions influence their interaction. It could be shown that already low amounts of Ca2+ strongly influence the interaction of hyaluronan with DPPC. Our results suggest that the calcium ions increase the amount of adsorbed hyaluronan indicating an increased electrostatic interaction. Most importantly, we observe a modification of the DPPC phase diagram as hyaluronan absorbs to the bilayer which results in an Lα-like structure at low temperatures and a decoupling of the leaflets forming an asymmetric bilayer structure. %0 journal article %@ 0001-8686 %A Dedinaite, A., Wieland, D.C.F., Beldowski, P., Claesson, P.M. %D 2019 %J Advances in Colloid and Interface Science %P 102050 %R doi:10.1016/j.cis.2019.102050 %T Biolubrication synergy: Hyaluronan – Phospholipid interactions at interfaces %U https://doi.org/10.1016/j.cis.2019.102050 %X The manner in which nature has solved lubrication issues has fascinated scientists for centuries, in particular when considering that lubrication is achieved in aqueous media. The most outstanding system in this respect is likely the synovial joint, where close to frictionless motion is realized under different loads and shear rates. This review article focuses on two components present in the synovial area, hyaluronan and phospholipids. We recapitulate what has been learned about their interactions at interfaces from recent experiments, with focus on results obtained using reflectivity techniques at large scale facilities. In parallel, modelling experiments have been carried out and from these efforts new detailed knowledge about how hyaluronan and phospholipids interact has been gained. In this review we combine findings from modelling and experiments to gain deeper insight. Finally, we summarize what has been learned of the lubrication performance of mixtures of phospholipids and hyaluronan. %0 journal article %@ 0169-4332 %A Bouali, A.C., Straumal, E.A., Serdechnova, M., Wieland, D.C.F., Starykevich, M., Blawert, C., Hammel, J.U., Lermontov, S.A., Ferreira, M.G.S., Zheludkevich, M.L. %D 2019 %J Applied Surface Science %P 829-840 %R doi:10.1016/j.apsusc.2019.07.117 %T Layered double hydroxide based active corrosion protective sealing of plasma electrolytic oxidation/sol-gel composite coating on AA2024 %U https://doi.org/10.1016/j.apsusc.2019.07.117 %X This work reports a novel approach for growing layered double hydroxide (LDH) films on any plasma electrolytic oxidation (PEO) coated AA2024 independently of the nature of the PEO coating. The specific PEO coating chosen to carry out this work is considered to be not suitable for direct LDH growth because of phase composition and morphological features. In this paper, we describe a new methodology that consists of covering the PEO coating with a thin layer of aluminum oxide based xerogel as the source of aluminate ions for subsequent in-situ LDH growth. X-ray diffraction (XRD) and scanning electron microscope (SEM) images showed a successful formation of LDHs on the surface. An improvement in terms of active corrosion protection was also demonstrated by electrochemical impedance spectroscopy (EIS) and scanning vibrating electrode technique (SVET). %0 lecture %@ %A Wieland, D.C.F. %D 2018 %J %T Strukturbiochemie %U %X %0 conference paper %@ %A Willumeit-Roemer, R., Moosmann, J., Zeller-Plumhoff, B., Wieland, D.C.F., Krueger, D., Wiese, B., Wennerberg, A., Peruzzi, N., Galli, S., Beckmann, F., Hammel, J.U. %D 2018 %J TMS 2018, 147th Annual Meeting & Exhibition, Supplemental Proceedings %P 275-284 %R doi:10.1007/978-3-319-72526-0_25 %T Visualization of Implant Failure by Synchrotron Tomography %U https://doi.org/10.1007/978-3-319-72526-0_25 %X Here we present first data from an in situ tomography experiment of a biodegradable Mg-based implant under compressive load showing how Mg implants are incorporated into bone. %0 conference poster %@ %A Moosmann, J., Hammel, J., Beckmann, F., Wilde, F., Dose, T., Burmester, H., Hipp, A., Peruzzi, N., Galli, S., Krueger, D., Zeller-Plumhoff, B., Wieland, F.D.C., Willumeit-Roemer, R. %D 2018 %J 13th International Conference on Synchrotron Radiation Instrumentation, SRI 2018 %T A load frame for in situ tomography at PETRA III %U %X %0 conference poster %@ %A Moosmann, J., Hammel, J., Beckmann, F., Wilde, F., Dose, T., Burmester, H., Hipp, A., Peruzzi, N., Galli, S., Krueger, D., Zeller-Plumhoff, B., Wieland, F.D.C., Willumeit-Roemer, R. %D 2018 %J Posters, 13th International Conference on Synchrotron Radiation Instrumentation, SRI 2018 %P 348 %T A load frame for in situ tomography at PETRA III %U %X We present a load frame for in situ experiments at the microtomography end stations at the imaging beamline (IBL) P05 and the high-energy material science (HEMS) beamline P07 of PETRA III at DESY, both operated by the Helmholtz-Zentrum Geesthacht. The load frame is highly flexible and modular and can be used in compression or tension mode applying forces of up to 1 kN and employing attenuation or phase-contrast techniques. We demonstrate its performance showing results from recent experiments investigating the failure of biodegradable Magnesium-based implants in rat bone under increasing load conditions. %0 conference lecture (invited) %@ %A Willumeit-Roemer, R., Moosmann, J., Zeller-Plumhoff, B., Wieland, D.C.F., Krueger, D., Wiese, B., Wennerberg, A., Peruzzi, N., Galli, S., Beckmann, F., Hammel, J.U. %D 2018 %J 10th International Conference on Processing and Manufacturing of Advanced Materials, THERMEC 2018 %T Magnesium as biodegradable implant materials: how does the interface react to load? %U %X %0 conference lecture %@ %A Wieland, D.C.F. %D 2018 %J 17th International Small Angle Scattering Conference, SAS 2018 %T Degradable Mg-Based Implans: Impact on the Ultrastructure of Bone %U %X %0 conference lecture (invited) %@ %A Wieland, D.C.F. %D 2018 %J Kolloquium Chemie Hamburg %T Synergistic Macromolecular Interactions in Synovial Fluids %U %X %0 conference lecture (invited) %@ %A Wieland, D.C.F. %D 2018 %J Kolloquium Chemie Kiel %T Interaction of proteins and polymers under pressure and shear %U %X %0 conference lecture (invited) %@ %A Wieland, D.C.F. %D 2018 %J Luebecker Summer Akademy %T Micro Fluidic System for the Investigation of the Synovial Liquid by X-ray Scattering Method %U %X %0 journal article %@ 2045-2322 %A Shulha, T.N., Serdechnova, M., Lamaka, S.V., Wieland, D.C.F., Lapko, K.N., Zheludkevich, M. %D 2018 %J Scientific Reports %P 16409 %R doi:10.1038/s41598-018-34751-7 %T Chelating agent-assisted in situ LDH growth on the surface of magnesium alloy %U https://doi.org/10.1038/s41598-018-34751-7 %X In situ formation of layered double hydroxides (LDH) on metallic surfaces has recently been considered a promising approach for protective conversion surface treatments for Al and Mg alloys. In the case of Mg-based substrates, the formation of LDH on the metal surface is normally performed in autoclave at high temperature (between 130 and 170 °C) and elevated pressure conditions. This hampers the industrial application of MgAl LDH to magnesium substrates. In this paper, the growth of MgAl LDH conversion coating directly on magnesium alloy AZ91 at ambient conditions (25 °C) or elevated temperatures is reported in carbonate free electrolyte for the first time. The direct LDH synthesis on Mg alloys is enabled by the presence of organic chelating agents (NTA and EDTA), which control the amount of free and/or hydroxyl bound Mg2+ and Al3+ in the solution. The application of the chelating agents help overcoming the typical technological limitations of direct LDH synthesis on Mg alloys. The selection of chelators and the optimization of the LDH treatment process are supported by the analysis of the thermodynamic chemical equilibria. %0 conference lecture %@ %A Willumeit-Roemer, R., Moosmann, J., Zeller-Plumhoff, B., Wieland, D.C.F., Krueger, D., Wiese, B., Wennerberg, A., Peruzzi, N., Galli, S., Beckmann, F., Hammel, J.U. %D 2018 %J 147th Annual Meeting & Exhibition, TMS 2018 %T Visualization of Implant Failure by Synchrotron Tomography %U