Entrainment and Detection of Engineered Nanoparticles

CBET-1236909拟议的研究通过两种方式解决了了解工作场所暴露于工程纳米颗粒的必要性：(I)通过研究工程纳米颗粒可能成为空气中的基本机制；以及(Ii)开发适合于常规工作场所的气溶胶仪器，并对1-500 nm尺寸范围的纳米颗粒进行个人监测，能够跟踪可能导致设计良好的纳米颗粒合成系统的大部分暴露的瞬变。还将进行受控实验室实验，以加深对纳米颗粒释放到空气中的机理的基本了解，首先研究纳米颗粒涂层表面的空气动力学携带。将通过开发一种小型、简单、低成本的纳米粒子相对迁移气溶胶探测器(NOMAD)来解决长期存在的监测工作场所暴露的适当仪器的需求，该探测器将能够以足够的分辨率评估暴露，以估计肺沉积模式。Nomad的性能将与纳米技术实验室中传统的暴露监测方法进行比较，并提供目前尚不可能的个人暴露数据。智力优势：拟议的研究将使用大小可分辨的仪器来调查空气中纳米颗粒的来源，与以前的研究相比，该仪器具有更好的时间响应和更广泛的潜在尺寸范围，从而能够检测到瞬时释放事件，并促进纳米颗粒源的识别。随后的受控实验室实验将量化从不同类型的表面沉积中携带纳米颗粒所需的力，以及由此产生的空气中纳米颗粒的团聚程度，从而为从根本上理解潜在的暴露机制奠定基础。新的仪器将使健康效应研究成为可能，这些研究显然是理解纳米技术风险所必需的，但由于目前仪器的成本和复杂性，目前还不可能。有了这些工具，持续暴露数据将成为健康效应研究和工人保护的宝贵工具。他们将进一步研究消费者纳米技术产品的使用和传统污染源对纳米颗粒的暴露。广泛影响：拟议的研究将为导致工程纳米颗粒释放到工作场所空气中的偶然过程以及与此类释放相关的风险提供新的见解。新的空气纳米粒子探测器将使研究人员和行业监管者能够以现在不可能的方式严格地监测纳米粒子的暴露。此外，这些新的探测器应该成为健康效应研究的使能技术，这些研究显然是必要的，但目前还不可能。本科生将有机会通过加州理工大学的暑期本科生研究奖学金(SURF)参与到这个项目中来。此外，弗拉根实验室将招募少数民族本科生研究奖学金(MURF)项目的参与者，就像过去6年中的4年一样。我们将与加州理工大学S外展项目合作，邀请当地学生到我们的实验室演讲和参观，并与他们学校的学生交谈。来自当地高中的学生，特别是那些靠近高速公路的学生，将被招募从事涉及家庭或学校环境中纳米颗粒测量的科学项目。就像他10年来所做的那样，PI将继续共同指导加利福尼亚州阿尔罕布拉市拉蒙纳修道院中学的First Robotics团队，这是一所有60%少数族裔入学的女子高中。事实证明，这是一种最有效的机制，通过向学生展示工程学是有趣的，来激发他们在大学里学习STEM的兴趣。

CBET-1236909The proposed research addresses the need to understand workplace exposures to engineered nanoparticlesin two ways: (i) by investigating fundamental mechanisms by which engineered nanoparticlesmay become airborne; and (ii) by developing aerosol instruments suitable for routine workplace andpersonal monitoring of nanoparticles in the 1-500 nm size range with the ability to follow transientthat may be responsible for most exposure from well-designed nanoparticle synthesis systems.Controlled laboratory experiments will also be conducted to develop a fundamental understandingof mechanisms for nanoparticle release to the air, beginning with studies of the aerodynamicentrainment from nanoparticle-coated surfaces. The long-standing need for suitable instrumentsfor monitoring workplace exposures will be addressed by creating a small, simple, and low costnanoparticle opposed migration aerosol detector (NOMAD) that will enable exposure assessmentwith sufficient resolution to estimate lung deposition patterns. The NOMAD performance will becompared with conventional approaches to exposure monitoring in nanotechnology laboratories, andprovide personal exposure data that is not presently possible.Intellectual merit: The proposed research will survey sources of airborne nanoparticles usingsize resolved instruments with better time response, and broader coverage of the potential sizerange than employed in previous studies, thereby enabling detection of transient release events, andfacilitating identification of nanoparticle sources. Subsequent controlled laboratory experiments willquantify the forces required to entrain nanoparticles from different kinds of surface deposits, and theextent of agglomeration the airborne nanoparticles that result, thereby laying the groundwork fora fundamental understanding of potential exposure mechanisms. The new instruments will enablehealth effects studies that are clearly needed to understand the risks of nanotechnology, but arenot presently possible due to the cost and complexity of present instruments. With these tools,continuous exposure data will become a valuable tool in both health effect research and in workerprotection. They will further enable studies of exposures to nanoparticles in the use of consumernanotechnology products, and from conventional pollution sources.Broader impacts: The proposed research will provide new insights into incidental processesthat contribute to the release of engineered nanoparticles into workplace air, and the risks associatedwith such releases. The new airborne nanoparticle detectors will enable researchers and industry tomonitor nanoparticle exposures with rigor that is not now possible. Moreover, these new detectorsshould become the enabling technology for health effects studies that are clearly needed, but notpresently possible.Undergraduates will have the opportunity to become involved in the project through Caltech?sSummer Undergraduate Research Fellowship (SURF). In addition, the Flagan laboratory will recruitparticipants from the Minority Undergraduate Research Fellowship (MURF) program as it has in4 of the last 6 years. We will work with Caltech?s outreach program to invite local area students tolectures and visits to our laboratory, as well as talk to the students in their schools. Students fromlocal high schools, particularly those near freeways, will be recruited to undertake science projectsinvolving measurements of nanoparticles in their home or school environments.As he has done for 10 years, the PI will continue to co-mentor a First Robotics team at RamonaConvent Secondary School, a girls high school in Alhambra, CA that has 60% minority enrollment.This has proven to be a most effective mechanism in stimulating interest in pursuing STEM studiesin college by showing the students that engineering is fun.