MOLECULAR MODELING STUDIES FOR DEVELOPMENT OF SENSORS FOR ORGANOPHOSPHATES

有机磷酸盐传感器开发的分子模型研究

• 批准号: 7381815
• 负责人: RAJENDRAN MOHANRAJ
• 金额: $ 3.7万
• 依托单位: MISSISSIPPI STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7381815
• 关键词: MOLECULAR; MODELING; STUDIES; DEVELOPMENT; SENSORS

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The present study involves the use of a sensor based on advances in nanotechnology and the use of liquid crystals to sense the presence of pesticides. Simulation approaches are being studied to improve the design of the sensor. As is the case with development of several nanotechnology applications, different problems are amenable to simulation studies performed at different length and time scales. For example, we are interested in improving the specificity of the sensor (ability to distinguish between similar analytes) as well as its sensitivity (ability to detect low concentrations of analyte). Molecular scale simulations are more suitable for understanding issues related to specificity and continuum scale simulations are more appropriate for estimating sensitivity. Whereas the earlier efforts in this investigation focused on molecular scale simulations, in the later stage more emphasis has been placed on use of continuum scale models. Unlike the studies involving molecular scale simulations for which commercial software was used, the effort in continuum scale modeling requires development of the software for performing the simulations. This model development incorporates the use of three-dimensional unstructured grids to model complex geometry, and, problem solving in a parallel environment to benefit from the use of large computer clusters for solving practical problem configurations. Test cases have been performed to obtain the orientation of the liquid crystal in the presence of analyte molecules. The analyte molecules have been modeled as spheres at present and will involve more realistic geometries in the future. The effect of concentration of the analyte on the optical pattern displayed by the liquid crystal medium has been studied by performing simulations at different concentrations. Such studies enable estimation of the minimum concentration of the analyte (the sensitivity of the sensor) that can be detected through changes caused in the optical pattern of the liquid crystal medium.

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。目前的研究涉及使用基于纳米技术进步的传感器和使用液晶来检测杀虫剂的存在。为了改进传感器的设计，正在研究模拟方法。就像几种纳米技术应用的发展一样，不同的问题适合于在不同的长度和时间尺度上进行的模拟研究。例如，我们感兴趣的是提高传感器的特异性(区分相似分析物的能力)和灵敏度(检测低浓度分析物的能力)。分子尺度模拟更适合于理解与特异性相关的问题，而连续尺度模拟更适合于估计灵敏度。鉴于这项研究的早期工作集中在分子尺度模拟上，在后期阶段更多地强调使用连续尺度模型。与使用商业软件进行分子尺度模拟的研究不同，连续介质尺度模拟的努力需要开发执行模拟的软件。这种模型开发结合了使用三维非结构网格来模拟复杂的几何图形，并在并行环境中解决问题，从而受益于使用大型计算机集群来解决实际问题配置。已经进行了测试，以在分析物分子存在的情况下获得液晶的取向。分析物分子目前被模拟为球体，未来将涉及更逼真的几何形状。通过在不同浓度下进行模拟，研究了分析物浓度对液晶介质显示的光学图样的影响。这样的研究能够估计通过液晶介质的光学图案引起的变化可以检测到的分析物的最小浓度(传感器的灵敏度)。