Collaborative Research in Nanostructure Control via Surfactant Mixing and Polymerization

通过表面活性剂混合和聚合控制纳米结构的合作研究

• 批准号: 0436195
• 负责人: Norman Wagner
• 金额: --
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-02-01 至 2009-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0436195&HistoricalAwards=false
• 关键词: Collaborative; Research; Nanostructure; Control; via

University of Delaware/ University of California Santa BarbaraABSTRACT - 0436195/0436124Project SummaryMuch of nanotechnology is devoted to creating two-dimensional structures on surfaces. However,learning the composition-structure-function relationships for biomimetic self-assembly will lead to nanoscale, three-dimensional vesicle structures for specific tasks including drug delivery, catalysis, specific recognition, among others. This proposal addresses the science and engineering needed to advance the self-assembly of functional nano-containers of polymers and surfactants, based on our group's expertise with the combining the physics and chemistry of nanostructures with the self-assembly and specific recognition processes of biology. The basic theme is centered on the self-assembly of oppositely charged surfactants and/or hydrotropes into unilamellar vesicles that can be fixed by polymerization to yield stable, hollow capsules that can be further functionalized. Specific aims are:1. Study the formation and polymerization of vesicles formed from polymerizable surfactants andorganic and inorganic monomers to best retain the size, shape and polydispersity of templating vesicles;2. Modify and control vesicle properties adding block co-polymers to adjust the spontaneous curvature (size), bending elasticity (polydispersity) and the steric interactions between vesicles (stability). In particular, near equimolar mixtures of polymerizable anionic and cationic surfactants with copolymers that likely create monodisperse vesicle systems will be formulated;3. Examine the novel properties of vesicles formed in mixtures of surfactant and hydrotropes (which are weakly surface-active, amphiphilic, and highly water-soluble organic salts), and to probe microstructural changes therein caused by changes in pH or light exposure.Project 1 will involve synthesis and formulation carried out primarily at U. Delaware by Kaler'sgroup and microscopy characterization at UCSB by Zasadzinski's group. The formulations needed for project 2 will be done at UCSB and characterization will be carried out using light scattering and electron microscopy by Zasadzinski's group, and neutron spin-echo and neutron scattering by Kaler's group. Project 3 will be initiated at U. Delaware by Kaler's group and characterized by microscopy done in Zasadzinski's group. The reduction in time from 3 to 2 years will cause us to not be able to get as far in the project; however, all of the specific aims will be examined and the most promising routes identified.Intellectual Merit: The self-assembly of oppositely charged surfactants and hydrotropes opens newareas of biomimetic structures for exploration, and will likely put the process of vesicle formation under thermodynamic control. Exploiting thermodynamic control means being able to determine the size, polydispersity, stability, etc. of vesicles by simple manipulation of simple, inexpensive detergents. Chemical reactions (i.e., polymerization) to fix such structures open new ways to form nanoscale materials that retain the nanostructure of the template. The proposed work expands and links these two areas, and will provide both novel experimental observations and further theoretical understanding.Technical Impact: Surfactant formulations, particularly surfactant mixtures, are widely used inmany industrial processes. The ability to control surfactant microstructure by mixing surfactants or adding hydrotropes could provide new organic templates for novel organic and inorganic materials such as polymer latices and molecular sieves. Manufacturing polymerized vesicles cheaply could open the way to high-volume usages in printing or agricultural applications. Work with spontaneous vesicles made of biological surfactants will lead to useful pharmaceutical applications. Controlling the aggregation and fusion of vesicles is of crucial importance to drug delivery schemes, as is minimization of the free surfactant concentration.Broader Impact: The scientific aspects of this proposed work will enable discovery of newnanoscale surfactant architectures through the development of and understanding of their thermodynamic and mechanical properties, including the nature of their equilibrium state. Study of these mixtures has already led to fruitful reexamination of many of the fundamental dogmas of self-assembly. Study of both organic and inorganic polymerizations can open ways to make new materials that could have application beyond those discussed above. Undergraduate and graduate students involved in this work will be exposed to a range of characterization tools and appropriate analytical methods, and thereby be prepared for either academic or industrial work in this area. K-12 students will be exposed to concepts relevant to this work, including surfactant and polymer properties and elements of nanotechnology.Statement of Effect of Time Reduction:We have proposed three specific aims:1. Study the formation and polymerization of vesicles formed from polymerizable surfactantsand organic and inorganic monomers to best retain the size, shape and polydispersity oftemplating vesicles;2. Modify and control vesicle properties adding block co-polymers to adjust the spontaneouscurvature (size), bending elasticity (polydispersity) and the steric interactions between vesicles(stability). In particular, near equimolar mixtures of polymerizable anionic and cationicsurfactants with copolymers that likely create monodisperse vesicle systems will be formulated;3. Examine the novel properties of vesicles formed in mixtures of surfactant and hydrotropes(which are weakly surface-active, amphiphilic, and highly water-soluble organic salts), and toprobe microstructural changes therein caused by changes in pH or light exposure.Project 1 will involve synthesis and formulation carried out primarily at U. Delaware by Kaler'sgroup and microscopy characterization at UCSB by Zasadzinski's group. The formulationsneeded for project 2 will be done at UCSB and characterization will be carried out using lightscattering and electron microscopy by Zasadzinski's group, and neutron spin-echo and neutronscattering by Kaler's group. Project 3 will be initiated at U. Delaware by Kaler's group andcharacterized by microscopy done in Zasadzinski's group. The reduction in time from 3 to 2years will cause us to not be able to get as far in the project; however, all of the specific aims willbe examined at some level and the most promising routes identified for subsequent proposals.

摘要：大部分纳米技术都致力于在表面上创建二维结构。然而，学习仿生自组装的组成-结构-功能关系将导致纳米尺度的三维囊泡结构用于特定任务，包括药物输送，催化，特异性识别等。本提案基于我们团队的专业知识，将纳米结构的物理和化学与生物学的自组装和特定识别过程相结合，解决了推进聚合物和表面活性剂功能纳米容器自组装所需的科学和工程问题。基本主题集中在带相反电荷的表面活性剂和/或疏水物的自组装成单层囊泡，这些囊泡可以通过聚合固定，从而产生稳定的空心胶囊，可以进一步功能化。具体目标是：1.；研究可聚合表面活性剂与有机和无机单体形成的囊泡的形成和聚合，以最好地保留模板囊泡的大小、形状和多分散性；通过添加嵌段共聚物来改变和控制囊泡性质，以调节自发曲率（尺寸）、弯曲弹性（多分散性）和囊泡间的空间相互作用（稳定性）。特别是，可聚合的阴离子和阳离子表面活性剂与共聚物的近等摩尔混合物，可能会形成单分散的囊泡系统；研究表面活性剂和亲水物（弱表面活性、两亲性和高水溶性有机盐）混合物中形成的囊泡的新特性，并探测其中由pH值变化或光照引起的微观结构变化。项目1将包括主要由Kaler小组在特拉华大学进行的合成和配方，以及由Zasadzinski小组在UCSB进行的显微镜表征。项目2所需的配方将在UCSB完成，Zasadzinski的团队将使用光散射和电子显微镜进行表征，Kaler的团队将使用中子自旋回波和中子散射进行表征。项目3将由Kaler的团队在特拉华大学发起，并由Zasadzinski的团队通过显微镜进行表征。时间从3年减少到2年将导致我们无法在项目中取得那么远的进展；但是，将审查所有具体目标，并确定最有希望的路线。智力优势：带相反电荷的表面活性剂和亲水剂的自组装为探索仿生结构开辟了新的领域，并有可能将囊泡形成过程置于热力学控制之下。利用热力学控制意味着能够通过简单、廉价的洗涤剂的简单操作来确定囊泡的大小、多分散性、稳定性等。固定这种结构的化学反应（即聚合）为形成保留模板纳米结构的纳米级材料开辟了新的途径。提出的工作扩展和连接这两个领域，并将提供新的实验观察和进一步的理论理解。技术影响：表面活性剂配方，特别是表面活性剂混合物，广泛应用于许多工业过程。通过混合表面活性剂或添加亲水剂来控制表面活性剂微观结构的能力可以为新型有机和无机材料（如聚合物晶格和分子筛）提供新的有机模板。廉价制造聚合囊泡可以为印刷或农业应用的大量使用开辟道路。研究由生物表面活性剂制成的自发囊泡将导致有用的制药应用。控制囊泡的聚集和融合对药物递送方案至关重要，同时也对最小化游离表面活性剂浓度至关重要。更广泛的影响：这项工作的科学方面将通过发展和理解纳米表面活性剂的热力学和机械性能，包括其平衡状态的性质，来发现新的纳米级表面活性剂结构。对这些混合物的研究已经导致了对自我组装的许多基本教条的富有成效的重新审视。有机和无机聚合的研究可以开辟新的途径，使新材料的应用可能超出上述讨论。参与这项工作的本科生和研究生将接触到一系列表征工具和适当的分析方法，从而为该领域的学术或工业工作做好准备。K-12学生将接触到与这项工作相关的概念，包括表面活性剂和聚合物性质以及纳米技术的元素。缩短时间的效果声明：我们提出了三个具体目标：1。研究可聚合表面活性剂与有机和无机单体形成的囊泡的形成和聚合，以最好地保留模板囊泡的大小、形状和多分散性；通过添加嵌段共聚物来修饰和控制囊泡性质，以调节囊泡的自发性质（尺寸）、弯曲弹性（多分散性）和空间相互作用（稳定性）。特别是，可聚合的阴离子和阳离子表面活性剂与共聚物的近等摩尔混合物，可能会形成单分散的囊泡系统；研究表面活性剂和亲水物（弱表面活性、两亲性和高水溶性有机盐）混合物中形成的囊泡的新特性，并探测其中由pH值变化或光照引起的微观结构变化。项目1将包括主要由Kaler小组在特拉华大学进行的合成和配方，以及由Zasadzinski小组在UCSB进行的显微镜表征。项目2所需的配方将在UCSB完成，Zasadzinski的团队将使用光散射和电子显微镜进行表征，Kaler的团队将使用中子自旋回波和中子散射。项目3将由Kaler的团队在特拉华大学发起，并由Zasadzinski的团队通过显微镜进行表征。将时间从3年减少到2年将导致我们无法在项目中取得那么远的进展；但是，将在某种程度上审查所有具体目标，并为后续提案确定最有希望的路线。