EAGER: A New Multiphoton Luminescence Imaging Approach to Interrogate the Fate of Metallic Nanoparticles in a Living System

EAGER：一种新的多光子发光成像方法来探究金属纳米粒子在生命系统中的命运

• 批准号: 2223834
• 负责人: Cristina Zavaleta
• 金额: $ 30万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-10-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2223834&HistoricalAwards=false
• 关键词: EAGER; New; Multiphoton; Luminescence; Imaging

Over the last 20 years, metallic nanoparticles have been utilized across a wide range of fields from cosmetics to renewable energy to electronics to biomedical applications. Their size gives them unique properties, and the use of metallic nanoparticles has revolutionized several technological and industrial sectors. As a result, inadvertent human exposure rates to engineered metallic nanoparticles are increasing, generating the need to better understand their short- and long-term effects to ensure the public’s safety. This project will focus on utilizing a new imaging strategy that can offer important insights on how metallic nanoparticles behave in living systems. The imaging strategy is different than conventional imaging techniques in that it does not require an exogenous label to track metallic nanoparticles. Instead, the imaging strategy can detect and follow the metallic nanoparticles in a label-free manner by exploiting a luminescent signal that is generated from the metals that comprise the nanoparticles themselves. The imaging technique can offer real-time tracking of metallic nanoparticles to observe their physiological interactions while in circulation. The images generated will also be able to reveal where they ultimately reside in the body and determine if any toxic effects or morphological changes are resulting. Gaining an improved fundamental understanding of these biological interactions could 1) better discern the safety of metallic nanomaterials in living subjects, 2) lead to informing new environmental policies, 3) generate new disease targeting strategies with therapeutic metallic nanoparticles to improve patient outcome. Additionally, further development and assessment of this transformative imaging strategy could open new avenues of investigation throughout the nano-community to further exploit this unique imaging technique. Local Los Angeles high school students will be introduced to the physical concepts and imaging approaches utilized here and the various nanoparticle types encountered as environmental pollutants. The goals for the educational plan are to 1) generate enthusiasm and spark creativity among students from under-represented groups in the Los Angeles area by showing different ways that nanoparticles are used to solve problems and 2) introduce new imaging concepts to students that can allow them to watch where nanoparticles are located in the body.The research objective of this project is to explore a new multiphoton luminescence imaging strategy and its ability to develop a deeper understanding of how metallic nanoparticles behave in living systems. Researchers have previously reported on specific endpoints of nanoparticle interactions studied in cell culture on a macroscopic scale, e.g., cellular stress, inflammatory or mutagenic responses, or biodistribution profiles observed in preclinical models. However, this does not give a complete or biologically accurate depiction of how nanomaterials behave in a dynamic living system. Metallic nanoparticle biodistribution has been previously studied, but their real-time dynamics in circulation and ultimate fate are poorly understood on the microscopic level. This research project addresses this critical need by using a new and innovative multiphoton luminescence microscopy imaging approach. Intravital microscopy (IVM) has emerged as a profound imaging modality for gaining insight into dynamic processes on the cellular and sub-cellular level and is particularly suitable for visualizing nanoparticles in real time. IVM has enabled observation of several fundamental nanoparticle processes such as extravasation, tumor accumulation, and blood elimination in real time within a living organism. A current problem is that most nanoparticles must be exogenously labeled with fluorophores for visualization with conventional single-photon IVM. As the fluorophore may dissociate from the nanoparticle, it is challenging to determine the true behavior of nanoparticles within the blood stream using this approach. This project will use a new label-free multiphoton luminescence imaging approach that was recently uncovered in the principal investigator’s (PI’s) lab to study the native behavior of metallic nanoparticles in mouse models. Intrinsic broad-band luminescence has previously been observed in noble metals under multiphoton excitation conditions but has yet to be applied successfully in vivo to track nanoparticles flowing within the vasculature in real time. Luminescent properties associated with metals have yet to be applied successfully in vivo to track nanoparticles flowing within the vasculature in real time. This underutilized intrinsic luminescence will be used to 1) track metallic nanoparticles flowing in the vasculature to assess their rates of clearance from blood, and 2) determine their toxicities on major organs where they ultimately reside by analyses of harvested tissues. This is an immensely powerful tool, as the intrinsic luminescence of metallic nanoparticles could finally give the research community the ability to follow native flow in the blood while providing dynamic physiological information and ultimately localizing their accumulation within tissues on a microscopic scale. Consumers may be inadvertently exposed to various metallic nanoparticles. The results generated from this project are meant to enable a better understanding of the cellular interactions taking place within the body and where these nanoparticles ultimately reside. This information will be important in determining how to better regulate these nanomaterials as new nano-enabled products are engineered. A multi-year outreach and educational training plan will be pursued that is closely integrated with the proposed research, emphasizing how people use and encounter nanomaterials day to day. High school students from underrepresented groups across the Los Angeles area will be introduced to nanoparticles and the imaging techniques utilized to study their interactions in the body. The PI will connect with a Hispanic serving institution in her hometown, University of Texas Rio Grande Valley (UTRGV). UTRGV currently lacks Ph.D. curricula in STEM and this research opportunity will enable the participation of these students in this research lab, providing interaction with Ph.D. students. This will promote higher education paths for students who otherwise would not get exposed to these careers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在过去的20年里，金属纳米颗粒被广泛应用于化妆品、可再生能源、电子产品和生物医学等领域。它们的尺寸赋予了它们独特的性能，金属纳米颗粒的使用已经彻底改变了几个技术和工业领域。因此，人类无意中暴露于工程金属纳米粒子的比率正在增加，因此需要更好地了解它们的短期和长期影响，以确保公众的安全。该项目将专注于利用一种新的成像策略，该策略可以为金属纳米颗粒在生命系统中的行为提供重要的见解。成像策略不同于传统的成像技术，因为它不需要外源标签来跟踪金属纳米颗粒。相反，该成像策略可以通过利用由组成纳米颗粒本身的金属产生的发光信号，以无标记的方式检测和跟踪金属纳米颗粒。成像技术可以实时跟踪金属纳米颗粒，观察它们在循环过程中的生理相互作用。生成的图像还将能够揭示它们最终在体内的位置，并确定是否有任何毒性作用或形态学变化。提高对这些生物相互作用的基本理解可以1)更好地辨别金属纳米材料在活体中的安全性，2)为新的环境政策提供信息，3)利用治疗性金属纳米颗粒产生新的疾病靶向策略，以改善患者的预后。此外，这种变革性成像策略的进一步发展和评估可以为整个纳米社区的研究开辟新的途径，以进一步利用这种独特的成像技术。洛杉矶当地的高中学生将被介绍到这里使用的物理概念和成像方法，以及作为环境污染物遇到的各种纳米颗粒类型。该教育计划的目标是：1)通过展示纳米粒子用于解决问题的不同方法，在洛杉矶地区代表性不足的群体中激发学生的热情和创造力；2)向学生介绍新的成像概念，使他们能够观察纳米粒子在体内的位置。该项目的研究目标是探索一种新的多光子发光成像策略及其能力，以深入了解金属纳米颗粒在生命系统中的行为。研究人员先前报道了在宏观尺度上研究细胞培养中纳米颗粒相互作用的特定终点，例如细胞应激、炎症或致突变反应，或在临床前模型中观察到的生物分布概况。然而，这并没有给出一个完整的或生物学上准确的描述纳米材料在动态生命系统中的行为。金属纳米颗粒的生物分布已经被研究过，但它们在微观层面上的实时动态循环和最终命运却知之甚少。这个研究项目通过使用一种新的和创新的多光子发光显微镜成像方法来解决这一关键需求。活体显微镜（IVM）已经成为一种深刻的成像方式，用于深入了解细胞和亚细胞水平的动态过程，特别适合于实时可视化纳米颗粒。IVM可以实时观察纳米颗粒的外渗、肿瘤积聚和血液消除等基本过程。目前的一个问题是，大多数纳米颗粒必须用荧光团外源标记，以便用传统的单光子IVM可视化。由于荧光团可能与纳米颗粒分离，因此使用这种方法确定纳米颗粒在血流中的真实行为具有挑战性。该项目将使用一种新的无标签多光子发光成像方法，该方法最近在首席研究员（PI）的实验室中发现，用于研究金属纳米颗粒在小鼠模型中的天然行为。在多光子激发条件下，贵金属的固有宽带发光已经被观察到，但尚未成功地应用于体内实时跟踪血管内流动的纳米颗粒。与金属相关的发光特性尚未在体内成功应用于实时跟踪血管内流动的纳米颗粒。这种未充分利用的固有发光将用于1)追踪金属纳米颗粒在脉管系统中的流动，以评估它们从血液中的清除率；2)通过分析收获的组织来确定它们对主要器官的毒性。这是一个非常强大的工具，因为金属纳米颗粒的固有发光最终可以使研究团体能够跟踪血液中的天然流动，同时提供动态生理信息，并最终在微观尺度上定位它们在组织内的积累。消费者可能无意中接触到各种金属纳米颗粒。这个项目产生的结果是为了更好地理解体内发生的细胞相互作用，以及这些纳米颗粒最终驻留在哪里。这些信息对于决定如何更好地管理这些纳米材料是很重要的，因为新的纳米产品被设计出来了。一项多年的推广和教育培训计划将与拟议的研究紧密结合，强调人们如何每天使用和接触纳米材料。来自洛杉矶地区代表性不足群体的高中生将被介绍纳米粒子和用于研究其在体内相互作用的成像技术。PI将与她家乡的西班牙裔服务机构德克萨斯大学格兰德谷分校（UTRGV）联系。UTRGV目前缺乏STEM的博士课程，这个研究机会将使这些学生能够参与这个研究实验室，提供与博士生的互动。这将为那些没有机会接触这些职业的学生提供更高的教育途径。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。