TY - JOUR A1 - Mans, C. A1 - Simons, C. A1 - Hanning, S. A1 - Janßen, A. A1 - Alber, D. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Bühler, A. A1 - Kreyenschmidt, M. T1 - New polymeric candidate reference materials for XRF and LA-ICP-MS - development and preliminary characterization N2 - A set of ten calibration materials based on acrylonitrile-butadiene-styrene terpolymer (ABS) containing the elements Br, Pb, Cd, Cr, and Hg was produced in order to control polymer samples in regard to the restriction on the use of certain hazardous substances (RoHS) directive. The materials were produced with respect to the special demands of X-ray fluorescence analysis (XRF) and inductively coupled plasma mass spectrometry in combination with laser ablation (LA-ICP-MS). The mass fractions of all elements were 0-1500 mg/kg and the materials were produced as granulates and solid discs with a diameter of 40 mm and thicknesses of 1, 2, and 6 mm. It could be shown that the signals measured by XRF strongly depend on the thickness of polymeric samples. Macroscopic homogeneity was assessed with XRF measuring a total of 180 samples. The microscopic homogeneities were determined for a material with average elemental mass fractions with the aid of synchrotron radiation (SR) µ-XRF and LA-ICP-MS. Sufficient macroscopic and microscopic homogeneities for all elements could be achieved. It was observed that organic additives show a better homogeneity than oxides. XRF and LA-ICP-MS were successfully calibrated with the new materials. Limits of detection were in the range of 0.4-22 mg/kg for XRF and 2.3-26.8 mg/kg for LA-ICP-MS. The materials are considered as candidate reference materials (RM) by the Federal Institute of Materials Research and Testing (BAM, Germany). KW - XRF KW - LA.ICP-MS Plastics KW - RoHS KW - CRM PY - 2009 DO - https://doi.org/10.1002/xrs.1120 SN - 0049-8246 VL - 38 IS - 1 SP - 52 EP - 57 PB - Wiley CY - Chichester AN - OPUS4-18681 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ostermann, Markus A1 - Berger, Achim A1 - Mans, C. A1 - Simons, C. A1 - Hanning, S. A1 - Janßen, A. A1 - Kreyenschmidt, M. T1 - Results and effects of homogeneity and stability studies carried out by X-ray fluorescence on the new reference material BAM-H010 N2 - The Federal Institute for materials research and testing (BAM)in cooperation with the Fachhochschule Münster has developed a new certified polymeric reference material, BAM-H010. The reference material consists of acrylonitrile–butadiene–styrene terpolymer (ABS) and has been doped with different contents of the elements Br, Cd, Cr, Hg and Pb. The monitoring of these elements is demanded in the EU directive 2002/95/EG, commonly referred to as RoHS. We have shown that the uncertainty contribution of the thermal long-term stability (ustability) is negligible compared to the contribution to the uncertainty caused by the method used for the characterization of the elemental content and the batch inhomogeneity (uhomogeneity). The stability of theABS material during exposure of the samples with hard X-radiation leads to a degradation of the ABS matrix with either long- or short-chain products. KW - Reference material KW - Plastic KW - RoHS KW - WEEE KW - X-ray fluorescence PY - 2011 DO - https://doi.org/10.1007/s00769-011-0806-x SN - 0949-1775 SN - 1432-0517 VL - 16 IS - 10 SP - 515 EP - 522 PB - Springer CY - Berlin AN - OPUS4-24249 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simons, C. A1 - Mans, C. A1 - Hanning, S. A1 - Janßen, A. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Ostermann, Markus A1 - Michaelis, Matthias A1 - Wienold, Julia A1 - Alber, D. A1 - Kreyenschmidt, M. T1 - Study on microscopic homogeneity of polymeric candidate reference materials BAM H001-BAM H010 by means of synchrotron µ-XRF and LA-ICP-MS N2 - In this study the microscopic homogeneity of the newly developed plastic reference materials BAM H001-BAM H010 was investigated. The materials consist of an acrylonitryle-butadien-styrene terpolymer, doped with different amounts of the elements Br, Cd, Cr, Hg and Pb. For the quantitative determination of the degree of homogeneity, a procedure proposed by Kempenaers et al. (Fresenius J. Anal. Chem., 2001, 369, 733-737) was used. On every sample an extensive number of different points were analyzed and standard deviation for every element mentioned above was used to calculate a minimal sampling mass that is necessary to reach a certain level of uncertainty caused by inhomogeneity (mmin,5%). The experiments were taken out with synchrotron µ-XRF (SR µ-XRF) at BESSYII in Berlin and by laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS). The calculated values for mmin,5% of both techniques showed comparable results for all elements. It could be shown that the materials are suitable for calibration of micro analytic techniques if at least 64 µg are used. KW - XRF KW - LA-ICP-MS KW - RoHS KW - CRM PY - 2010 DO - https://doi.org/10.1039/b917008a SN - 0267-9477 SN - 1364-5544 VL - 25 SP - 40 EP - 43 PB - Royal Society of Chemistry CY - London AN - OPUS4-20938 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Winkler, T. A1 - Hoenig, E. A1 - Huber, G. A1 - Janssen, R. A1 - Fritsch, D. A1 - Gildenhaar, Renate A1 - Berger, Georg A1 - Morlock, M.M. A1 - Schilling, A.F. T1 - Osteoclastic bioresorption of biomaterials: Two- and three-dimensional imaging and quantification N2 - Purpose: Bioresorbable materials have been developed in the hope that the body will replace them with newly formed tissue. The first step of this remodeling process in bone is the bioresorption of the material by osteoclasts. The aim of this study was to analyze osteoclastic resorption of biomaterials in vitro using the commonly used two-dimensional methods of light-microscopy (LM) and scanning electron microscopy (SEM) in comparison with infinite focus microscopy (IFM), a recently developed imaging method allowing for three-dimensional surface analysis. Methods: Human hematopoietic stem cells were cultivated in the presence of the cytokines M-CSF and RANK-L for 4 weeks directly on dentin and a calcium phosphate cement. Osteoclast development was surveyed with standard techniques. After removal of the cells, resorption was characterized and quantified by LM, SEM and IFM. Results: Osteoclast cultures on the biomaterials presented the typical osteoclast-specific markers. On dentin samples LM, SEM as well as IFM allowed for discrimination of resorption. Quantification of the resorbed area showed a linear correlation between the results (LM vs. SEM: r=0.996, p=0.004; SEM vs. IFM: r=0.989, p=0.011; IFM vs. LM: r=0.995). It was not possible to demarcate resorption pits on GB14 using LM or SEM. With IFM, resorption on GB14 could be visualized and quantified two- and three-dimensionally. KW - Biomaterial KW - Three-dimensional KW - IFM KW - Osteoclast KW - Dentin KW - Calcium phosphate PY - 2010 SN - 0391-3988 VL - 33 IS - 4 SP - 198 EP - 203 PB - Wichtig Ed. CY - Milano [u.a.] AN - OPUS4-21621 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Winkler, T. A1 - Hoenig, E. A1 - Gildenhaar, Renate A1 - Berger, Georg A1 - Fritsch, D. A1 - Janssen, R. A1 - Morlock, M.M. A1 - Schilling, A.F. T1 - Volumetric analysis of osteoclastic bioresorption of calcium phosphate ceramics with different solubilities N2 - Commonly, to determine osteoclastic resorption of biomaterials only the resorbed area is measured. The depth of the resorption pit, however, may also be important for the performance of a material. To generate such data we used two calcium phosphate ceramics (Ca10 and Ca2). The solubility of the materials was determined according to DIN EN ISO 10993-14. They were scanned three-dimensionally using infinite focus microscopy and subsequently cultivated for 4 weeks in simulated body fluid without (control) or with human osteoclasts. After this cultivation period osteoclasts number was determined and surface changes were evaluated two- and three-dimensionally. Ca10 and Ca2 showed solubilities of 11.0 ± 0.5 and 23.0 ± 2.2 mg g-1, respectively. Both materials induced a significant increase in osteoclast number. While Ca10 did not show osteoclastic resorption, Ca2 showed an increased pit area and pit volume due to osteoclastic action. This was caused by an increased average pit depth and an increased number of pits, while the average area of single pits did not change significantly. The deduced volumetric osteoclastic resorption rate (vORR) of Ca2 (0.01–0.02 µm3 µm-2 day-1) was lower than the remodelling speed observed in vivo (0.08 µm3 µm-2 day-1), which is in line with the observation that implanted resorbable materials remain in the body longer than originally expected. Determination of volumetric indices of osteoclastic resorption might be valuable in obtaining additional information about cellular resorption of bone substitute materials. This may help facilitate the development of novel materials for bone substitution. KW - Biodegradation KW - Surface analysis KW - Simulated body fluid KW - Osteoclasts KW - Calcium phosphate ceramics PY - 2010 DO - https://doi.org/10.1016/j.actbio.2010.04.015 SN - 1742-7061 VL - 6 IS - 10 SP - 4127 EP - 4135 PB - Elsevier CY - Amsterdam AN - OPUS4-22554 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -