TY - JOUR A1 - Gorbushina, Anna A1 - Kempe, A. A1 - Rodenacker, K. A1 - Jütting, U. A1 - Altermann, W. A1 - Stark, R.W. A1 - Heckl, W.M. A1 - Krumbein, W.E. T1 - Quantitative 3-dimensional image analysis of mineral surface modifications - chemical, mechanical and biological JF - Geomicrobiology journal N2 - Three principally different mechanisms contribute to the wear-down process of mineral aggregates in sedimentary environments: (1) mechanical abrasion by forces of wind and water and by floating or saltating neighbouring grains, (2) chemical attack and dissolution by fluids, and (3) physical bioerosion and chemical biocorrosion. It is however, difficult to attribute the specific surface changes to specific environments and processes. Quartz sand grains from subaerial and subaquatic environments were analysed by atomic force microscopy (AFM) for traces of natural and experimental aeolian, aquatic and biological wear-down processes. Quantitative topographical parameters of surface alterations were extracted from topography data by non-linear methods derived from digital image analysis. These parameters were examined by multivariate statistic, yielding three well-distinguishable groups. Morphological surface alterations dominated by subaerial, subaquatic and by biological impact could be differentiated. The method may also be used for the detection of aeolian, subaquatic, and biological modification of sedimentary grains and rock surfaces in extraterrestrial environments, and for assessment of environmental damage on monuments and buildings. KW - Sediment grain corrosion KW - Chemical grain pitting KW - Biological grain pitting KW - Aquatic grain corrosion KW - Biopitting KW - Weathering KW - Surface analysis KW - Nano-structure of grain and mineral surfaces PY - 2011 DO - https://doi.org/10.1080/01490451.2010.490077 SN - 0149-0451 VL - 28 SP - 1 EP - 13 PB - Crane, Russak & Co. CY - New York, NY, USA AN - OPUS4-23058 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lukowiak, M.C. A1 - Wettmarshausen, Sascha A1 - Hidde, Gundula A1 - Landsberger, Petra A1 - Boenke, Viola A1 - Rodenacker, K. A1 - Braun, Ulrike A1 - Friedrich, Jörg Florian A1 - Gorbushina, Anna A1 - Haag, R. T1 - Polyglycerol coated polypropylene surfaces for protein and bacteria resistance JF - Polymer chemistry N2 - Polyglycerol (PG) coated polypropylene (PP) films were synthesized in a two-step approach that involved plasma bromination and subsequently grafting hyperbranched polyglycerols with very few amino functionalities. The influence of different molecular weights and density of reactive linkers were investigated for the grafted PGs. Longer bromination times and higher amounts of linkers on the surface afforded long-term stability. The protein adsorption and bacteria attachment of the PP-PG films were studied. Their extremely low amine content proved to be beneficial for preventing bacteria attachment. PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-325406 DO - https://doi.org/10.1039/c4py01375a SN - 1759-9954 SN - 1759-9962 VL - 6 IS - 8 SP - 1350 EP - 1359 AN - OPUS4-32540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Menzel, Friederike A1 - Conradi, Bianca A1 - Rodenacker, K. A1 - Gorbushina, Anna A1 - Schwibbert, Karin ED - Menzel, Friederike T1 - Flow chamber system for the statistical evaluation of bacterial colonization on materials JF - Materials N2 - Biofilm formation on materials leads to high costs in industrial processes, as well as in medical applications. This fact has stimulated interest in the development of new materials with improved surfaces to reduce bacterial colonization. Standardized tests relying on statistical evidence are indispensable to evaluate the quality and safety of these new materials. We describe here a flow chamber system for biofilm cultivation under controlled conditions with a total capacity for testing up to 32 samples in parallel. In order to quantify the surface colonization, bacterial cells were DAPI (4‘,6-diamidino-2-phenylindole)-stained and examined with epifluorescence microscopy. More than 100 images of each sample were automatically taken and the surface coverage was estimated using the free open source software g’mic, followed by a precise statistical evaluation. Overview images of all gathered pictures were generated to dissect the colonization characteristics of the selected model organism Escherichia coli W3310 on different materials (glass and implant steel). With our approach, differences in bacterial colonization on different materials can be quantified in a statistically validated manner. This reliable test procedure will support the design of improved materials for medical, industrial, and environmental (subaquatic or subaerial) applications. KW - Subaerial and subaquatic biofilm KW - Escherichia coli KW - Image analysis KW - Microscopy KW - Biofilm KW - Biofouling PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-377040 DO - https://doi.org/10.3390/ma9090770 SN - 1996-1944 VL - 9 IS - 9 SP - 770 AN - OPUS4-37704 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -