NER: Magnetically Activated Nanoporous Structures for Biomedical Applications

NER：用于生物医学应用的磁激活纳米孔结构

• 批准号: 0210033
• 负责人: Craig Grimes
• 金额: $ 9万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2004-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0210033&HistoricalAwards=false
• 关键词: NER; Magnetically; Activated; Nanoporous; Structures

This proposal was received in response to the Nanoscale Science and Engineering Initiative, Program Solicitation NSF 01-157, in the NER category. The proposal focuses on innovative materials synthesis strategies to create both passive, and magnetically-driven mechanically active precision separation membranes. Of particular interest is the development and characterization of well-controlled, stable, and uniform nano-dimensional membranes capable of the separation of viruses and/or proteins during the blood fractionation processes and the blocking of antibodies and complement molecules from encapsulated xenogeneic cells. It is hypothesized that high surface area cylindrical capsules the walls of which are comprised of nanoporous membranes, created via a two-step process of electric-field driven anodization of aluminum or titanium, can be used for the absolute filtration or exclusion of biomolecules in the nanometer range. For a given capsule, a windowpane structure is used with anodized nanoporous windows, and un-anodized aluminum struts for structural support. The aluminum anodization process enables precise control of pore size, with a controllable pore diameter of approximately 10 nm to 100 nm depending upon anodizing voltage. Beyond making passive membranes, the investigators propose fabrication of cylindrical nanoporous biocapsules incorporating magnetoelastic elements. Incorporation of the magnetoelastic elements enable the biocapsule to be mechanically vibrated, remotely from a distance, by application of a time-varying magnetic field that should enable controlled transport through the membrane. A magnetoelastic thick film layer will be electroplated onto the aluminum structural supports of the capsule. Such capsules could possibly find application as in-vivo drug delivery devices, where needed medicine is delivered in precise amounts by external application of a magnetic field. As a further aspect of the proposed research, the investigators seek to build upon their expertise in fabrication of nanoporous alumina films of high uniformity to fabricate surface coatings comprised of perpendicularly oriented gold-coated magnetostrictive nanowire arrays. The utility of these arrays will be investigated for their utility in prevention of biofouling. It is hypothesized that the needle-like shape of the nanowire array elements, and the wave-like movement of the magnetostrictive nanowire array in response to a time-varying non-uniform magnetic field, will help prevent protein attachment to the surface, and could ultimately be used to move or transfer cells across the surface. The proposed research will determine optimal routes for fabrication of the nanoporous capsules with attention to membrane functionality as biological filters. The application of passive nanoporous biocapsules for cellular encapsulation and immunoisolation, and mechanically active biocapsules for controlled transport and delivery through the nanoporous membranes will be investigated. In addition, the use of magnetostrictive nanowire arrays will be investigated for their use in the prevention of biofouling. The proposed outcomes are: (1) Determining a path for in-situ or in-vivo controlled drug delivery by application of an external time varying magnetic field. (2) Determination of a surface that would prevent biofouling, facilitating the introduction of medical devices into the human body.

该提案是响应纳米科学与工程倡议，计划征求NSF 01-157，在NER类别。 该提案的重点是创新的材料合成策略，以创建被动和磁驱动的机械主动精密分离膜。特别令人感兴趣的是良好控制的，稳定的，和均匀的纳米尺寸的膜的开发和表征，能够分离的病毒和/或蛋白质在血液分馏过程中和抗体和补体分子的封闭从封装异种细胞。 据推测，其壁由纳米多孔膜组成的高表面积圆柱形胶囊，通过铝或钛的电场驱动阳极氧化的两步法产生，可用于绝对过滤或排除纳米范围内的生物分子。 对于给定的胶囊，窗玻璃结构与阳极化的纳米多孔窗口一起使用，并且未阳极化的铝支柱用于结构支撑。 铝阳极氧化工艺能够精确控制孔径，根据阳极氧化电压，孔径可控制在约10 nm至100 nm之间。 除了制造被动膜，研究人员还提出了制造包含磁弹性元件的圆柱形纳米多孔生物胶囊。 磁致弹性元件的结合使得生物胶囊能够通过施加时变磁场而远离一定距离地机械振动，所述时变磁场应当能够控制通过膜的运输。 磁致弹性厚膜层将被电镀到胶囊的铝结构支撑件上。 这种胶囊可能会被用作体内药物输送装置，其中所需的药物通过外部施加磁场以精确的量输送。 作为所提出的研究的另一个方面，研究人员试图建立在他们的专业知识，在制造纳米多孔氧化铝膜的高度均匀性，制造表面涂层组成的垂直取向的金涂层的磁致伸缩纳米线阵列。 这些阵列的效用将被调查，其效用在防止生物污损。 假设纳米线阵列元件的针状形状和磁致伸缩纳米线阵列响应于时变非均匀磁场的波浪状运动将有助于防止蛋白质附着到表面，并且最终可以用于在表面上移动或转移细胞。拟议的研究将确定制造纳米多孔胶囊的最佳路线，并注意作为生物过滤器的膜功能。 将研究用于细胞封装和免疫隔离的被动纳米多孔生物胶囊和用于通过纳米多孔膜的受控运输和递送的机械活性生物胶囊的应用。 此外，磁致伸缩纳米线阵列的使用将被调查用于防止生物污垢。 拟议的成果是：（1）通过施加外部时变磁场来确定用于原位或体内受控药物递送的路径。 (2)确定防止生物污染的表面，促进医疗器械进入人体。