The potential use of Sporosarcina pasteurii in possible biotechnological applications on a large scale (ground improvement, consolidation of building structures and ornamental stone, or in developing bio-materials for the building industry), is based on its ability to produce high amounts of carbonate in a short period of time via urea hydrolysis. Industrial biomass production would have a low environmental impact and would be most economical if the standard growth media could be replaced with alternative nutrient sources, such as byproducts or wastes from other industries, or other low cost ingredients. The use of cost effective ingredients must guarantee ureolytic activities and growth conditions that are comparable to those resulting from the standard nutrient medium. In this work, three types of alternative media were tested for growing the ureolytic active bacteria S. pasteurii: (1) alternative nutrient sources such as industrial wastes resulting from the dairy and brewery industries, (2) fertilizer urea as an alternative urea substitute, and (3) different types of poultry manure based fertilizers as nutrient and urea substitutes. The comparison between the standard media, the nutrient alternatives and urea substitutes was possible by taking the protein concentration and nitrogen content into account. Bacterial activity was evaluated in terms of biomass changes over time (CFU, optical density, ATP measurements) and indirect estimation of the enzyme production (Nessler assay, conductivity measurement). The results revealed that some of the dairy wastes tested, such as whey and buttermilk, are potential alternative nutrients for bacterial development, while the urea fertilizer is perfectly suitable as an economical substitute for pure laboratory grade urea.

Copper(II) oxalate was grown on carboxy-terminated self-assembled monolayers using a step-by-step approach by dipping the surfaces alternately in ethanolic solutions of copper(II) acetate and oxalic acid with intermediate thorough rinsing steps. The deposition was monitored by reflection absorption infrared spectroscopy (RAIRS), a quartz microbalance with dissipation measurement (QCM-D), scanning electron microscopy (SEM), and helium ion microscopy (HIM). Amounts of material corresponding to a coverage of 75% of a monolayer are deposited in each dipping step in copper(II) acetate solution while deposition of oxalic acid produces a viscoelastic layer that is partially removed by rinsing. This points toward initial aggregation but acid not bound to Cu(2+) ions as oxalate ions is removed by the rinsing steps. RAIRS further indicates that the material grows as copper(II) oxalate ribbons similar to the crystal structure but with ribbons oriented roughly parallel to the surface. SEM and HIM give evidence of the formation of needle-shaped structures which are a possible explanation for the viscoelastic behavior of the layer.

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The adsorption behavior of the Tet-124 antimicrobial peptide and the Tet-124peptide modified at the C- and N-terminus with the sequence glycine-3,4-dihydroxyphenylalanine-glycine (G-DOPA-G) on titanium surfaces was studied using quartz crystal micro balance with dissipation (QCM-D). At a low pH level(4.75) Tet-124 and Tet-124-G-DOPA-G form rigid layers. This is attributed to the electrostatic interactions of the positively charged lysine and arginine residues in the peptide sequence with the negatively charged titanium oxide layer. At an elevated pH level (6.9) Tet-124 shows a lower mass adsorption at the surface than Tet-124-G-DOPA-G. This is attributed to the interaction of the catechol due to the formation of complexes with the titanium oxide and titanium surface layer. The C terminal and N terminal modification with the sequence G-DOPA-G shows similar adsorption rate and mass adsorption coverage at saturation; however it is presented a more loosely layers on the G-DOPA-G-TeT-124. Fibroblast adhesion and the biocompatibility test of both the surfaces following modification withTet-124-G-DOPA-G and the titanium alloy control showed similar results. In addition, no changes in the adhesion of E. colibacteria due to the modification of the surface were detected

Dental implants coated with a durable and antibacterial film Vogel et al. embedded between two layers of PP by means of subsequent plasma polymerization and metal evaporation steps. The double PP/Ag/PP layer can be directly deposited on titanium implants, whose in vivo biocompatibility within soft tissues has been investigated in Ref. 13 .Building up on these previous results, in this article, we investigate the performances of a similar PP/Ag/PP-layered coating material (briefly, PP+Ag) toward the adhesion of bacteria and eukaryotic cells in vitro. In particular, besides HeLa cellular models, the adhesion behavior of fibroblasts and osteoblasts will be addressed. With respect to the original coating procedure, 12,13 physical vapor deposition is used instead of evaporation to deposit the silver nanoparticle layer. The advantage of the physical vapor deposition is a better control and reproducibility of the nanoparticle distribution and a lesser degree of nanoparticle agglomeration. We test the coating layer resistance to sterilization and implantation into bone tissue (Section 3.2), optimize the plasma deposition parameters to guarantee eukaryotic adhesion (Section 3.3) and check the successful bacterial deterrence of the coating in fluorescence microscopy images (Section 3.4). Materials and methods Plasma polymerization and layer formationThe plasma polymerization and deposition of silver nanoparticles are performed in the same plasma reactor chamber. A sample holder with rotating platforms is mounted inside a 125-liter vacuum chamber. The chamber comprises an electrode of rectangular shape and a silver target situated behind a shutter system. Gas inlets for the HMDSO precursor (Wacker, Munich, Germany), argon, oxygen and hydrogen (Linde AG, Pullach, Germany) and a pumping system are connected to the chamber walls. In this study, three different coating layers are investigated: (a) A 2000-nm-thick polymer coating without silver particles, which possesses cell-repelling properties (PP2000); (b) a 100-nm-thick coating without silver particles, which promotes eukaryotic adhesion (PP100) and (c) the same coating including silver nanoparticles to inhibit bacterial growth but not eukaryotic adhesion (PP100+Ag). The coating layers are produced as follows: After decreasing the chamber pressure below 10 −4 mbar, HMDSO and oxygen are injected to a working pressure of 10 −2 to 10 −3 mbar. Applying a power of 160 W for 120 s, the plasma is ignited, and a 50-nm-thick polymer preconditioning layer is formed. The 2000-nm-thick coating is prepared at 120 W and oxygen to HMDSO gas flow ratio of 1:2. On top of the preconditioning layer, either the plasma polymerization is carried on until the desired thickness is reached (e.g. 100 nm for PP100), or an intermediate layer of silver nanoparticles is deposited by applying a power of 200 W for 60 s between the silver target and the chamber walls.With this procedure, we coat sand-blasted and etched titanium dental implant screws (11·5-mm length, 5·5-mm diameter ) as well as titaniu...