Cytocompatibility of high nitrogen nickel-free stainless steel （HNS） with different nitrogen content was evalu- ated and compared with a conventional austenitic stainless steel 317L. The MTT assay （3-（4,5-dimethyl...Cytocompatibility of high nitrogen nickel-free stainless steel （HNS） with different nitrogen content was evalu- ated and compared with a conventional austenitic stainless steel 317L. The MTT assay （3-（4,5-dimethylthiazol- 2-yl）-2,5-diphenyltetrazolium bromide） was performed on MG63 osteoblasts to assess the cytotoxicity. The expression of selected marker typical of differentiated osteoblasts, such as alkaline phosphatase activity （AKP）, was also monitored in MG63 cells cultured on the tested materials. As a result, HNS had higher cell growth than 317L; meanwhile the cytocompatibility was increased with increasing nitrogen content. Furthermore, HNS enhanced osteoblasts differentiation, as confirmed by AKP activity. Overall these facts indicated that HNS had higher cytocompatibility than 317L and the nitrogen content contributed to the higher cytocompatibility of HNS. The influence of nitrogen on surface energy further explained the cytocompatibility of HNS.展开更多
In this work, surface activation of automotive polymers using atmospheric pressure plasmas was investigated. The aim was to increase the polar fraction of the surface energy of both plane and convex polymer devices wi...In this work, surface activation of automotive polymers using atmospheric pressure plasmas was investigated. The aim was to increase the polar fraction of the surface energy of both plane and convex polymer devices with a radius in the range of 30 mm. For this purpose, a fittable low temperature atmospheric pressure plasma source based on capacitively coupled multi-pin electrodes was set up and applied. Each single electrode generates a treatment spot of approximately 2 cm2 with a tunable power density of up to 1.4 W/cm2. The surface energy was evaluated by contact angle measurements. After treatment at a low energy density of 1.01 J/cm2, the polar fraction of the surface energy of the investigated polymers was increased by a factor of 3.3 to 132, depending on the polymer materials. It was shown that by applying the presented fittable plasma source, this effect is independent of the surface radius of the polymer sample.展开更多
基金supported by the National Natural Science Foundation of China (No. 31000428)the National Basic Research Program of China ("973 Program",No. 2012CB619101)
文摘Cytocompatibility of high nitrogen nickel-free stainless steel （HNS） with different nitrogen content was evalu- ated and compared with a conventional austenitic stainless steel 317L. The MTT assay （3-（4,5-dimethylthiazol- 2-yl）-2,5-diphenyltetrazolium bromide） was performed on MG63 osteoblasts to assess the cytotoxicity. The expression of selected marker typical of differentiated osteoblasts, such as alkaline phosphatase activity （AKP）, was also monitored in MG63 cells cultured on the tested materials. As a result, HNS had higher cell growth than 317L; meanwhile the cytocompatibility was increased with increasing nitrogen content. Furthermore, HNS enhanced osteoblasts differentiation, as confirmed by AKP activity. Overall these facts indicated that HNS had higher cytocompatibility than 317L and the nitrogen content contributed to the higher cytocompatibility of HNS. The influence of nitrogen on surface energy further explained the cytocompatibility of HNS.
基金supported by the European Regional Development Funds(EFRE)and the Workgroup Innovative Projects of Lower Saxony(AGiP) in the Frame of the Lower Saxony Innovation Network for Plasma Technology(NIP),Project Funding Reference Number W2-80029388
文摘In this work, surface activation of automotive polymers using atmospheric pressure plasmas was investigated. The aim was to increase the polar fraction of the surface energy of both plane and convex polymer devices with a radius in the range of 30 mm. For this purpose, a fittable low temperature atmospheric pressure plasma source based on capacitively coupled multi-pin electrodes was set up and applied. Each single electrode generates a treatment spot of approximately 2 cm2 with a tunable power density of up to 1.4 W/cm2. The surface energy was evaluated by contact angle measurements. After treatment at a low energy density of 1.01 J/cm2, the polar fraction of the surface energy of the investigated polymers was increased by a factor of 3.3 to 132, depending on the polymer materials. It was shown that by applying the presented fittable plasma source, this effect is independent of the surface radius of the polymer sample.
