XPS-Study of Metal-Polymer Interfaces After Polymer Surface Treatment by Ion and Plasma Techniques
A study of the effects of surface treatment of polypropylene on the deposition of thin metal films is presented. The polypropylene samples were treated in a low-pressure air plasma in one case and sputtered by argon ions in the other case. XPS was used to detect compositional surface modifications. Plasma treatment leads to surface oxidation, whereas the sputtering results in oxygen-free surfaces for in-situ analysis. After surface treatment, thin films of Mg, Ca and Ce were deposited. Depending on the surface treatment, we find indications for different bonding mechanisms and very different sticking probabilities. For the case of oxidized surfaces, the formation of a metal-oxygen-polymer complex is anticipated, whereas for oxygen-free surfaces a metal-carbon bond is likely to be formed.
Background ::: Spontaneously metastatic xenograft models of cancer are infrequent and the few that exist are resource intensive. In xenografts, caliper measurements can be used to determine primary tumor burden and response to therapy but in metastatic disease models determination of the presence of metastatic disease, metastatic burden, and response to therapy are difficult, often requiring serial necropsy. In this study we characterized the development of visceral metastases in a patient derived xenograft model (PDXM) using in vivo imaging.