SST: Novel Sensor Platforms Based on the Structural Integration of an Organic Light-Emitting Device, a Luminescent Sensing Element, and a Thin Film Si-Based Photodetector

该提案的目的是开发新颖的基于光致发光（PL）的传感器，该传感器在结构上完全集成：光源、感测元件和光电检测器（PD）以及相关的滤波器被制造在透明基板上并背对背地附接。因此，所得到的传感器可以是非常紧凑的，坚固的，选择性的，快速的，自主的，消耗很少的功率，并且便宜。该提案的重点是感测氧气，这是医学，环境，（生物）化学和食品监测的关键工具，以及炭疽杆菌毒素（炭疽）。中心概念是上述组件的新颖的总结构集成。光源是有机发光器件（OLED）像素的阵列。感测元件包括具有嵌入染料的多孔膜、PL选择性地对分析物敏感的表面固定物种、或具有溶液中的识别元件的微流体通道/威尔斯。PD和滤波器是氢化纳米晶Si、SiGe和/或SiC的多层薄膜。几何形状将是“后检测”，即，OLED和PD像素制造在基板的同一侧上。首先制造长通滤波器和PD像素的阵列，然后在PD像素之间的间隙中制造OLED。感测元件被制造在单独的基板上并附接到OLED/PD基板。在完整的设备中，电子电路（包括指令接收器和数据发送器）、读出器和电池将位于PD“后面”。因此，整个设备将是~2.5“x5“x1”，比目前可用的任何传感器都要紧凑得多，成本也更低。这项工作为基于PL的传感器提供了一个新的平台，可以进一步发展为多分析物传感器微阵列。创新元素是（i）所有传感器组件的完全集成，以及（ii）利用针对特定识别分子定制的微流体架构和膜/表面开发传感元件，这将提高灵敏度并缩短响应时间。此外，OLED将以脉冲模式运行，这将增加其寿命并产生可忽略不计的热量，这对于热敏识别元件和试剂至关重要。氧气将通过PL寿命进行监测，从而消除了频繁校准的需要。将评估不同的方法，以生成适用于实际应用的强大传感器。氧传感器将基于氧敏感染料的PL的动态猝灭，最初使用绿色OLED和Pt八乙基卟啉（PtOEP）染料。我们将比较染料嵌入固体膜和染料溶液的传感器。炭疽传感器将基于炭疽致死因子对某些肽的切割。标记的肽将在爱荷华州州立大学（ISU）的蛋白质设施（Protein Facility）合成，在切割位点的两侧具有福斯特共振能量转移供体和受体。上述两种试剂的传感器将是国土安全、医疗、环境、生物、食品/酿造和健康/安全等领域广泛应用的理想选择。除了这些影响之外，这些设备还为化学和生物制剂定义了一个新的传感器平台，这可能导致非常紧凑和廉价的多分析物传感器微阵列。拟议的工作将作为开发该平台的基础。它还将扩展嵌入/固定识别元件，传感器设计和传感器工程的基础知识。它还将产生广泛的教育影响，促进ISU跨学科生物物理学项目的发展，并培养凝聚态物理，电气工程，生物物理，化学和分子生物学方面的学生。通过为研究生开发新的实验课程模块，将其与教学相结合。计划让包括少数民族和妇女在内的大学生大量参与。

0428220ShinarThe objective of this proposal is to develop novel photoluminescence (PL)-based sensors that are fully structurally integrated: The light source, the sensing element, and the photodetector (PD) and associated filter, are fabricated on transparent substrates and attached back-to-back. The resulting sensors could therefore be extremely compact, robust, selective, fast, autonomous, consume little power, and inexpensive. The proposal focuses on sensing oxygen, a key tool in medical, environmental, (bio)chemical, and food monitoring, and Bacillus anthracis toxin (anthrax).The intellectual merit. The central concept is the novel total structural integration of the foregoing components. The light source is an array of organic light-emitting device (OLED) pixels. The sensing elements include porous films with an embedded dye, surface immobilized species whose PL is selectively analyte-sensitive, or microfluidic channels/wells with recognition elements in solution. The PD and filter are multilayer thin films of hydrogenated nanocrystalline Si, SiGe, and/or SiC. The geometry will be "back detection," i.e., the OLED and PD pixels are fabricated on the same side of the substrate. The array of long-pass filters and PD pixels is fabricated first, followed by the OLEDs in the gaps between the PD pixels. The sensing element is fabricated on a separate substrate and attached to the OLED/PD substrate. In the complete device, the electronic circuitry (including instruction receiver and data transmitter), readout, and battery will be positioned "behind" the PD. Hence the whole device would be ~2.5"x5"x1", far more compact and less costly than any sensors currently available. The work results in a new platform for PL-based sensors, which can be further developed to multianalyte sensor microarrays. Innovative elements are (i) the complete integration of all the sensor components, and (ii) the development of sensing elements utilizing microfluidic architectures and films/surfaces tailored for specific recognition molecules, which will enhance the sensitivity and shorten the response time. Moreover, the OLEDs will be operated in a pulsed mode, which will increase their lifetime and generate negligible heat, which is crucial for heat-sensitive recognition elements and agents. Oxygen will be monitored via the PL lifetime, thus eliminating the need for frequent calibration.Different approaches will be evaluated to generate robust sensors for real-world applications. The oxygen sensor will be based on the dynamical quenching of the PL of oxygen-sensitive dyes, initially with a green OLED and Pt octaethyl porphyrin (PtOEP) dye. We will compare the sensors with dyes embedded in solid films with dyes solutions. The anthrax sensor will be based on the cleavage of certain peptides by anthrax lethal factor. Labeled peptides will be synthesized at the Protein Facility of Iowa State University (ISU), with a Forster resonance energy transfer donor and acceptor on either side of the cleavage site.The broader impacts. The sensors for the two aforementioned agents will be ideal for a broad range of applications in areas such as homeland security, medical, environmental, biological, food/brewing, and health/safety. Beyond these impacts, the devices define a new sensor platform for chemical and biological agents, which could lead to extremely compact and inexpensive multianalyte sensor microarrays. The proposed work will serve as a basis for the development of this platform. It will also expand the basic knowledge in embedding/immobilizing recognition elements, sensor design, and sensor engineering. It will also have a broad educational impact, promoting the growth of the interdisciplinary biophysics program at ISU and training students in condensed matter physics, electrical engineering, biophysics, chemistry, and molecular biology. It will be integrated with teaching by developing new experimental course modules for graduate students. Significant participation of undergraduates, including minorities and women, is planned.