Abstract: Surface biofunctionalization is a common strategy to improve the material-tissue interface of inert implant surfaces. In this context we coated alumina-toughened zirconia (ATZ) ceramics after titanium plasma spraying with two different porous calcium phosphate layers and subsequently functionalized the obtained surfaces either with an RGD containing cell adhesion peptide sequence or a bone morphogenetic protein (BMP)-glycosaminoglycan complex. We studied initial cell adhesion densities, integrin expression, and alkaline phosphatase activity as an osteogenic marker of the coatings in vitro in comparison to the non-functionalized ATZ ceramics to evaluate the bone ingrowth potential of these biofunctionalized implant coatings.
Abstract: Laser shock processing (LSP) is increasingly applied as an effective technology for the improvement of metallic materials’ mechanical and surface properties in different types of components, mostly as a means of enhancement of their fatigue life behavior. As reported in previous contributions by the authors, a main effect resulting from the application of the LSP technique consists in the generation of relatively deep compression residual stresses fields into metallic components allowing an improved mechanical behaviour. On the other hand, Mg and its alloys have gained increasing relevance as natural biomaterials as their mechanical properties are in the same range as those corresponding to natural bone as well as due to their inherent bioabsorbable properties. In the present paper, the application of the LSP technology to biocompatible bioabsorbable Mg alloys suitable for chirurgical implementation is envisaged, the experimental verification of the residual stresses fields induced and the experimental characterization of the surface properties introduced by means of the treatment being specifically considered.
Abstract: Bone displays an amazing capacity for endogenous self-remodeling. However, compromised bone healing and recovering is on the ascent because of population aging, expanding rate of bone injury and the clinical requirement for the advancement of elective choices to autologous bone unions. Current strategies, including biomolecules, cell treatments, biomaterials and diverse combinations of these, are presently created to encourage the vascularization and the engraftment of the grafts, to reproduce at last a bone tissue with similar properties and attributes of the local bone. In this review, we look through the current techniques that are right now created, utilizing biomolecules, cells and biomaterials, to initiate, coordinate and potentiate bone regeneration and healing after damage and further talk about the natural procedures related with this repair.
Abstract: In-vitro cell culture offers the ability to grow individual cells and monitor their behaviour in a controlled environment over a certain time. During culture, different parameters have to be controlled to ensure a vital growth of cells. The most important parameters are temperature, pH-value, oxygen and carbon dioxide levels as well as the glucose concentration. All of these parameters influence the growth ability of the cell culture and should be monitored online. The online monitoring of glucose was achieved with a novel GOD based sensor which enabled a real-time measurement of glucose during cell culture. A first-time characterisation of the sensor was carried out in the culture medium DMEM. In addition, material properties of the culture system were investigated. At first to establish a baseline measurement, the sensor was placed in different glucose concentrations dissolved in Water-KCl mixture at 25 °C inside a batch chamber under constant stirring. Afterwards, the temperature was increased to 37 °C to simulate a cell culture environment. In addition, the system was transferred into a flow-through reaction chamber. The highest response signal and the most stable signal was achieved at 37 °C with DMEM during flow-through measurement. Based on these measurements online glucose monitoring in cell culture was possible to determine the glucose consumption for each cell which is important for future human-on-a-chip devices to prevent diabetic metabolisms.
Abstract: Several techniques have been employed to attach/detach cells to/from a substrate. Cells cultured on a substrate are generally detached from the substrate into a sheet by the destruction of protein between the cells and the substrate using enzymes such as trypsin. However, the enzymes also damage the adhesion molecules among the cells. TiO2 is an n-type semiconductor with an energy band gap of 3.0-3.2 eV, which displays a photocatalytic activity under ultraviolet (UV) light. The purpose of this work was to fabricate photo-responsive cell culture vessel using TiO2 film and to investigate adhesion behaviour of cells on it. TiO2 films were prepared on SiO2 plates by a sol-gel method using titanium tetraisopropoxide. Primary osteoblasts were seeded on the vessels and then incubated at 37 °C. During the incubation, UV irradiation was performed continuously from back-side of the vessels. Basically the number of cells monotonically increased with incubation periods under darkness. Previous light irradiation promoted the cell adhesion on the surface. The formation of Ti-OH groups on the TiO2 seems to be facilitated by the UV irradiation. In contrast, the cells decreased under continuous light irradiation. The cells were not exposed to UV in the vessels since it was completely absorbed by the TiO2 layer. It might be due to generated photocurrent or hydroxyl radicals on the TiO2 surface. These results imply that the adhesion/proliferation/detachment behaviours of cells can be controlled by the photocatalytic reaction of TiO2 and the irradiation patterns.
Abstract: Modern medical science delivers through innovative chemical or mechanical/physical means new strategies to treat patients mildly and fight diseases accurately. In line with this development a screening procedure for tissue samples under usage of the electronic speckle pattern interferometry is developed at the University of Applied Science Wildau. The paper at hand provides the corner stone for such a procedure in form of an incubation system that is adapted to the properties of an electronic speckle pattern interferometer and allows the incubation as well as study of samples over time. As a result the developed system can regulate its own temperature and is constructed for use in an electronic speckle pattern interferometry (ESPI) setup. Its design allows a simple modular approach for further development
Abstract: The sample preparation for biological and chemical probes involves following a strict workflow to eliminate any contamination to the sample beforehand. Furthermore, it is time consuming and must be carried out by trained personnel such as a nurse or other supervisors, making it therefore expensive. The development of novel sample preparation techniques paired with modern sample analysis systems is focused on improving the operability while keeping a constant quality of results. This is important to analyse samples, which cannot be determined with current screening conditions. The analysis of analytes is required to receive a more detailed picture of the patient and to fully understand its complexity. Possible samples for in-depth analysis of chemical origin can be cholesterol or glucose. More complex samples, such as blood or saliva, require a sophisticated system, which analyses the samples for their individual compounds.
Abstract: Smartphones are developing into all-purposes devices. In the present work, the employment/application of smartphones as medical devices in home care and point-of-care (POC) diagnostics are investigated in the analysis of Lateral Flow Assays (LFA). A smartphone-based LFA reader was developed for the quantitative analysis of D-Dimer – a biomarker indicating e.g. thrombotic event or danger of embolism.The proof-of-concept has been shown with multiple smartphones in establishing: (I) Optimal dimensions of the LFA cell of 72.11mm distance of smartphone to D-Dimer test leading to a coefficients of variances (CV) between 0.8% and 4.2%. (II) Inter-device investigations: CVs around 13.5%; a limit of detection (LOD) of 100ng/ml (DDU) D-Dimer. (III) Inter-smartphone investigations: CV about 16%, a limit of detection (LOD) at 66.4ng/ml (DDU). (IV) Calibrations: CV and LOD of three smartphones are comparable to the commercial available LFA reader. Further development to put the multiple smartphone-based LFA reader on the market.
Abstract: Surgical implantation of metallic stents is today a common procedure for restoring narrowed arteries. However, main complications as in-stent restenosis, partial or total thrombosis, inflammation and devices degradation are still a serious clinical concern. The coating of stents with fluorocarbon (CFx) ultrathin films represents a valuable strategy to limit these complications. Moreover, an additional step for the modification of some key surface properties of CFx coatings could further enhance their blood compatibility. Therefore, the objective of this work was to develop an oxidation process specific to ultrathin CFx coatings based on a methanol plasma treatment to modulate their biological response. Oxidized and non-oxidized coatings were investigated by XPS, ToF-SIMS, water contact angle, SEM and AFM. Tunable oxidation of the surface of CFx coatings was obtained by methanol plasma treatment, thus producing an increase of surface wettability, without affecting morphology, roughness and adhesion of the coatings. Blood test results showed an increased hemocompatibility of the oxidized samples, confirming the hypothesis that such treatment can succeed in modulating the blood contact behavior of the CFx oxidized coatings.