Daggumati Pallavi, Kurtulus Ozge, Chapman Christopher Abbott Reece, Dimlioglu Damla, Seker Erkin
Department of Electrical and Computer Engineering, University of California, Davis, USA.
J Vis Exp. 2013 Jul 15(77):e50678. doi: 10.3791/50678.
Nanostructured materials with feature sizes in tens of nanometers have enhanced the performance of several technologies, including fuel cells, biosensors, biomedical device coatings, and drug delivery tools. Nanoporous gold (np-Au), produced by a nano-scale self-assembly process, is a relatively new material that exhibits large effective surface area, high electrical conductivity, and catalytic activity. These properties have made np-Au an attractive material to scientific community. Most studies on np-Au employ macro-scale specimens and focus on fundamental science of the material and its catalytic and sensor applications. The macro-scale specimens limit np-Au's potential in miniaturized systems, including biomedical devices. In order to address these issues, we initially describe two different methods to micropattern np-Au thin films on rigid substrates. The first method employs manually-produced stencil masks for creating millimeter-scale np-Au patterns, while the second method uses lift-off photolithography to pattern sub-millimeter-scale patterns. As the np-Au thin films are obtained by sputter-deposition process, they are compatible with conventional microfabrication techniques, thereby amenable to facile integration into microsystems. These systems include electrically-addressable biosensor platforms that benefit from high effective surface area, electrical conductivity, and gold-thiol-based surface bioconjugation. We describe cell culture, immunostaining, and image processing techniques to quantify np-Au's interaction with mammalian cells, which is an important performance parameter for some biosensors. We expect that the techniques illustrated here will assist the integration of np-Au in platforms at various length-scales and in numerous applications, including biosensors, energy storage systems, and catalysts.
特征尺寸在几十纳米的纳米结构材料提升了包括燃料电池、生物传感器、生物医学设备涂层和药物递送工具在内的多种技术的性能。通过纳米级自组装过程制备的纳米多孔金（np-Au）是一种相对较新的材料，具有较大的有效表面积、高电导率和催化活性。这些特性使np-Au成为科学界有吸引力的材料。大多数关于np-Au的研究采用宏观尺度的样本，并专注于该材料的基础科学及其催化和传感器应用。宏观尺度的样本限制了np-Au在包括生物医学设备在内的小型化系统中的潜力。为了解决这些问题，我们首先描述了两种在刚性基板上微图案化np-Au薄膜的不同方法。第一种方法采用手工制作的模板掩膜来创建毫米级的np-Au图案，而第二种方法使用剥离光刻技术来图案化亚毫米级的图案。由于np-Au薄膜是通过溅射沉积工艺获得的，它们与传统的微加工技术兼容，因此便于轻松集成到微系统中。这些系统包括受益于高有效表面积、电导率和基于金硫醇的表面生物共轭的电寻址生物传感器平台。我们描述了细胞培养、免疫染色和图像处理技术，以量化np-Au与哺乳动物细胞的相互作用，这是一些生物传感器的重要性能参数。我们期望这里展示的技术将有助于np-Au在各种长度尺度的平台以及包括生物传感器、能量存储系统和催化剂在内的众多应用中的集成。
