CAREER: Harnessing continuous growth mechanism to synthesize water-soluble magnetic nanoparticles for magnetic particle imaging

非技术总结：该职业奖由材料研究部生物材料项目支持，旨在了解水溶性磁性纳米颗粒（MNPs）的持续生长机制，并利用生长机制合成用于磁性颗粒成像（MPI）应用的MNPs。该项目通过促进科学进步和促进公共卫生服务于国家利益。MPI是一种很有前途的新型成像方式，因为它可以直接从MNPs产生正对比信号，而不使用有害的电离辐射。MPI具有无限的组织穿透深度，低背景信号和高灵敏度。然而，MPI目前还不能用于临床应用。一个主要障碍是缺乏mpi特异性MNPs作为示踪剂。高性能MNPs对于实现MPI在临床转化中的潜力至关重要。该项目的灵感来自赵永峰教授的试点研究，该研究表明水溶性MNPs可以以连续生长的方式合成。所得到的MNPs具有较高的MPI性能。然而，持续生长的机制尚不清楚，水溶性MNPs与MPI性能之间的相关性尚未建立。解决这些问题将加速MPI高性能MNPs的设计、合成和制造。从该项目中获得的知识将刺激水溶性MNPs的受控合成，并为MPI在医疗保健中的应用扫清障碍。该项目将把拟议的研究活动与教育计划结合起来，以培养代表性不足的学生获得高等学位。外展计划是在密西西比国家科学博物馆的年度科学制造者活动期间向公众传播研究成果。技术概述：本研究的总体目标是获得水溶性磁性纳米颗粒（MNPs）在多元醇中连续生长机制的整体分子水平理解，旨在提高MNPs的磁性颗粒成像（MPI）性能。该研究项目意义重大，因为MPI是一种新兴的示踪成像方式，可以克服现有成像技术的许多局限性。MNPs的特性决定了其灵敏度和分辨率，这对MPI的进一步应用至关重要。为了实现这一总体目标，本项目旨在1)探索水溶性MNPs受控合成的持续生长机制；2)揭示多元醇中MNPs的动态生长概况；3)调整水溶性MNPs合成的反应参数；4)拓展了掺杂物合成水溶性MNPs的机理；5)研究多元醇合成MNPs的MPI性能。该项目将加速MPI高性能MNPs的选择、合成和制造。教育计划是将该研究项目与一项教育计划相结合，该计划旨在系统地培训杰克逊州立大学（JSU） STEM领域的少数民族本科生获得高级学位。该项目将通过布鲁克海文国家实验室（BNL）与JSU提供的课程相结合。JSU的学生将与BNL的研究科学家互动，学习最先进的材料表征技术。这项研究将作为“You be the Chemist”比赛的一部分进行展示，并有助于培养和提高中学生对STEM的热情。该项目由生物材料计划和促进竞争性研究的既定计划（EPSCoR）共同资助。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。

Non-technical summary: This CAREER award supported by the Biomaterials program in the Division of Materials Research aims to understand the continuous growth mechanism of water-soluble magnetic nanoparticles (MNPs) and harness the growth mechanism to synthesize MNPs for magnetic particles imaging (MPI) application. The project serves the national interest by promoting the progress of science and advancing public health. The MPI is a promising and novel imaging modality because it can generate positive contrast signals directly from MNPs without using harmful ionizing radiation. The MPI has unlimited tissue penetration depth, low background signals, and high sensitivity. Nevertheless, the MPI is currently not available for clinical applications. One major obstacle is a lack of MPI-specific MNPs as tracers. High-performance MNPs are critical to materialize the potential of MPI in clinical translation. This project is inspired by Professor Yongfeng Zhao’s pilot study demonstrating that water-soluble MNPs can be synthesized in a continuous growth manner. The resulting MNPs show high MPI performance. However, the mechanism of the continuous growth is still unknown, and the correlation between water-soluble MNPs and MPI performance is not established. Addressing these questions will accelerate the design, synthesis, and manufacturing of high-performance MNPs for MPI. The knowledge obtained from this project will stimulate the controlled synthesis of water-soluble MNPs and clear the roadblock for the application of MPI in healthcare. This project will integrate the proposed research activities with education plans to train underrepresented students for advanced degrees. The outreach plan is to disseminate the research findings to the general public during the annual Science Maker event in the Mississippi Museum of National Science. Technical summary:The overarching goal of this proposal is to obtain a holistic molecule-level understanding of the continuous growth mechanism of water-soluble magnetic nanoparticles (MNPs) in polyols, aimed to enhance magnetic particles imaging (MPI) performance of MNPs. The research project is meaningful because MPI is an emerging tracer imaging modality that can overcome many limitations of existing imaging techniques. The properties of MNPs dictate their sensitivity and resolution, which are essential for the further application of MPI. To achieve this overarching goal, this project is designed to 1) explore the continuous growth mechanism for controlled synthesis of water-soluble MNPs; 2) unravel a living growth profile of MNPs in polyols; 3) manipulate the reaction parameters for the synthesis of water-soluble MNPs; 4) expand the mechanism to synthesize water-soluble MNPs with dopants; and 5) study the MPI properties of MNPs synthesized in polyols. This project will accelerate the selection, synthesis, and manufacturing of high-performance MNPs for MPI. The education plan is to integrate this research project with an education initiative that is designed to systematically train minority undergraduate students in the STEM area at Jackson State University (JSU) to obtain advanced degrees. The project will be integrated with a course offered at JSU through the Brookhaven National Laboratory (BNL). JSU students will interact with research scientists from BNL and learn state-of-the-art technologies on materials characterization. This research will be presented as part of the “You Be The Chemist” competition and help foster and enhance the passion for STEM among middle school students.This project is jointly funded by the Biomaterials program and the Established Program to Stimulate Competitive Research (EPSCoR).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.