Collaborative Research: An Enzyme-free Amplification Technique for Ultrasensitive ELISA of Disease Biomarkers

疾病诊断技术对提高我们的生活水平至关重要。提高诊断技术的检测灵敏度可以更早地诊断疾病，特别是癌症和传染病，从而改善治疗结果。该项目的目标是通过开发基于纳米颗粒的信号放大技术来建立一个高灵敏度的诊断平台。拟议研究计划的更广泛影响包括对研究生和本科生，特别是来自代表性不足的群体的多学科培训，以及指导当地高中生和两个研究所之间的学生交流等外联活动。几十年来，酶联免疫吸附试验(ELISA)技术已在研究实验室和临床诊断中广泛使用。然而，近年来，它的检测限并没有得到实质性的提高。这项工作旨在开发一种新的无酶信号放大技术，可以显著提高ELISA的检测灵敏度。这项技术依赖于数百万个预先装载在金泡中的微小纳米颗粒的释放。每个释放的纳米颗粒都可以比酶联免疫吸附试验中常用的酶更有效地催化比色反应。通过用这种纳米颗粒包裹的金小泡取代常规的酶，建立了一种灵敏度大大提高的无酶酶联免疫吸附试验。为了优化信号放大系统，从而提高相关的无酶酶联免疫吸附试验的检测灵敏度，将仔细控制纳米粒和金泡的物理化学性质。为实现本项目的目标，将开展以下研究工作：1)建立基于纳米颗粒的信号放大体系；2)建立无酶EL ISA；3)将无酶EL ISA应用于检测添加了生物标志物标准的人体血液样品。信号放大技术有望冲击体外诊断的一般领域，并在生物医学中找到广泛的应用。该项目将有利于研究生和本科生，特别是妇女和少数民族，参与研究。这项研究也将被整合到针对K-12学生的外展活动中。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Technologies for diagnosis of diseases are essential to the improvement of our standard of living. Increasing detection sensitivity of a diagnostic technology can enable earlier diagnosis of diseases especially cancers and infectious diseases, thus improving treatment outcomes. The goal of this project is to establish a highly sensitive diagnostic platform through the development of a nanoparticle-based signal amplification technique. The broader impacts of the proposed research program include multidisciplinary training for graduate and undergraduate students particularly from underrepresented groups, as well as outreach activities such as mentoring local high-school students and student exchange between two institutes in summer.Enzyme-linked immunosorbent assay (ELISA) technology has been extensively used in research labs and clinical diagnostics for decades. However, its limit of detection has not been substantially improved in recent years. The proposed work seeks to develop a novel enzyme-free signal amplification technique that can substantially enhance the detection sensitivity of ELISA. This technique relies on the release of millions of tiny nanoparticles preloaded in gold vesicles. Each released nanoparticle can catalyze colorimetric reaction more effectively than a commonly-used enzyme in an ELISA. By substituting enzymes in a conventional ELISA with such nanoparticles-encapsulated gold vesicles, an enzyme-free ELISA with substantially enhanced sensitivity is established. To optimize the signal amplification system and thus enhance the detection sensitivity of associated enzyme-free ELISA, physicochemical properties of both nanoparticles and gold vesicles will be carefully controlled. To achieve the goal of this project, following research aims will be pursued: 1) Building the nanoparticles based signal amplification system; 2) Establishing the enzyme-free ELISA; and 3) Applying the enzyme-free ELISA to detecting human blood samples spiked with biomarker standards. The signal amplification technique is expected to impact the general field of in-vitro diagnostics and find a broad range of applications in biomedicine. This project will benefit the engagement of graduate and undergraduate students, especially women and minorities, into research. The research will also be integrated into outreach activities for K-12 students.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.