SGER: Exploratory studies of atmospheric-pressure glow plasma processing of bio-degradable polymer microparticles

SGER：大气压辉光等离子体处理生物可降解聚合物微粒的探索性研究

• 批准号: 0511817
• 负责人: Laxminarayan Raja
• 金额: $ 3.03万
• 依托单位: University of Texas at Austin
• 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: 2005-09-15 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0511817&HistoricalAwards=false
• 关键词: SGER; Exploratory; studies; atmospheric; pressure

Public AbstractCTS-0511817SGER: Exploratory studies of atmospheric-pressure glow plasma processing of bio-degradable polymer microparticlesPIs: Laxminarayan L Raja and Krishnendu RoyInstitution: University of Texas at AustinDiscovery of atmospheric-pressure glow (APG) discharges have created promising new avenues for plasma-based materials processing technologies. APG discharges have non-equilibrium thermal and chemical properties similar to classical low-pressure glow discharges, albeit under one-atmosphere and room-temperature conditions. Consequently, continuous processing of delicate/soft materials, particulate materials, and even materials in the liquid form are possible without need for expensive vacuum equipment. We have recently proposed a novel application of these discharges in the processing of biodegradable polymer microparticles. These polymer microparticles are used as vehicles for drug/vaccine delivery into the human body. An important step in the processing of these drug-laden particles is to activate them with a negative charge on their surface. Currently, this is achieved through a wet chemical processes that are inefficient, poorly reproducible, and engender undesirable liquid waste by-products. An APG plasma-based dry, efficient, and high-throughput process for the surface functionalization of bio-degradable polymer microparticles can address many of the problems with the wet-chemical processing approach. Here we propose to demonstrate the feasibility of using APG discharges for anionic surface activation of polymer microparticles. This exploratory research will comprise the following activities: 1) we will develop a flexible, high-throughput APG plasma-based technique for the processing of biopolymer microparticles. 2) Reactive APG plasmas involving helium working gas and oxygen additives will be used to demonstrate the potential for negative charge activation of the microparticles. 3) Several detailed aspects of the APG plasma-particle processing technique will be explored by employing a host of plasma diagnostic and materials characterization techniques. Plasma diagnostics include electrical characterization by measuring discharge voltage-current waveforms, optical imaging, and optical emission spectroscopy. Materials characterization will be performed by measuring particle zeta potentials, scanning electron microscopy imaging, and X-ray photoelectron spectroscopy for particle surface elemental analysis. Two important areas of technical impact are envisioned: 1) APG plasma discharge technology will be impacted through realization of an important material processing application for this relatively new class of discharges. Although numerous applications have been proposed ranging from the deposition/etching of materials to plasma flow control, APG discharge technology is yet to witness a successful and widespread application in the industry. 2) The existing technology for the manufacture of biopolymer drug-delivery microparticles will be impacted by the replacement of a crucial "wet chemistry-based" process step with an environmentally benign "dry" plasma-based process. We hope that successful demonstration of this process will serve as a motivation for additional research into plasma-based dry replacement technologies for biomaterials manufacture (a field that is currently dominated by wet processing approaches). We anticipate that this exploratory research will serve as precursor to a more systematic, long-term fundamental study of the unique aspects of the APG plasma-biopolymer processing technique.

公共摘要CTS-0511817 SGER：探索性研究大气压辉光等离子体处理的生物降解聚合物微粒PI：Laxminarayan L Raja和Krishnendu罗伊机构：德克萨斯大学奥斯汀分校大气压辉光（APG）放电的发现为等离子体基材料处理技术创造了有前途的新途径。APG放电具有类似于经典低压辉光放电的非平衡热和化学性质，尽管是在一个大气压和室温条件下。因此，可以连续处理精细/柔软材料、颗粒材料，甚至是液体形式的材料，而不需要昂贵的真空设备。我们最近提出了一种新的应用这些放电在生物降解聚合物微粒的处理。这些聚合物微粒用作药物/疫苗递送到人体中的载体。处理这些载药颗粒的一个重要步骤是用表面上的负电荷激活它们。目前，这是通过湿化学方法实现的，该方法效率低、可再现性差，并且产生不期望的液体废物副产物。用于生物可降解聚合物微粒的表面官能化的基于APG等离子体的干燥、高效和高通量方法可以解决湿化学处理方法的许多问题。在这里，我们建议证明使用APG放电的聚合物微粒的阴离子表面活化的可行性。这项探索性研究将包括以下活动：1）我们将开发一种灵活的，高通量的APG等离子体技术，用于处理生物聚合物微粒。2)反应APG等离子体涉及氦工作气体和氧添加剂将被用来证明负电荷激活的微粒的潜力。3)APG等离子体粒子处理技术的几个详细方面将采用等离子体诊断和材料表征技术的主机进行探讨。等离子体诊断包括通过测量放电电压-电流波形、光学成像和光学发射光谱进行的电气表征。将通过测量颗粒zeta电位、扫描电子显微镜成像和用于颗粒表面元素分析的X射线光电子能谱来进行材料表征。设想了两个重要的技术影响领域：1）APG等离子体放电技术将通过实现这一相对较新的放电类别的重要材料加工应用而受到影响。尽管已经提出了从材料的沉积/蚀刻到等离子体流动控制的许多应用，但APG放电技术尚未在工业中成功和广泛应用。2)现有的生物聚合物药物递送微粒的制造技术将受到用环境友好的“干”等离子体工艺替代关键的“基于湿化学”工艺步骤的影响。我们希望这一过程的成功演示将成为对用于生物材料制造的基于等离子体的干式替代技术（目前由湿法加工方法主导的领域）进行更多研究的动力。我们预计，这项探索性研究将作为对APG等离子体生物聚合物加工技术的独特方面进行更系统，长期基础研究的先驱。