Collaborative Research: A Low-Cost, "Digital" Biosensing Platform with Single Protein Biomarker Sensitivity

蛋白质的精确测量对现代生物医学研究至关重要，特别是对疾病的早期检测和监测、系统生物学和新药开发。更具体、敏感、特异、快速和低成本地检测患者样本中的蛋白质生物标志物对公共卫生很重要，也是未来个性化诊断和治疗的关键组成部分。迄今为止，酶联免疫吸附法是检测蛋白质生物标志物最常用的传感技术。然而，由于灵敏度低，需要校准图来阐明结果，以及需要昂贵的先进仪器进行超灵敏测量，因此仍然存在许多限制，大大限制了它们的广泛应用。该提案旨在通过开发一种简单、低成本、但潜在强大的传感器来解决上述缺点，该传感器基于两级信号放大传感机制和机器学习可靠性的集成。所开发的传感设备特别适合早期疾病检测，理想情况下能够“数字化”（无需校准）检测生物标志物的存在，具有出色的可移植性、适应性、准确性和高通量。从这项研究中获得的知识和技术将传播给科学界和工业界。该项目将通过将先进的生物传感知识整合到他们的教育和实验室培训中，并积极与公众和行业公司互动，影响研究生，本科生和高中生的教育。所提出的传感装置将允许免疫分析作为一种低成本和数字（无需校准）检测技术进行，通过集成三个关键组件，具有潜在的单拷贝灵敏度：1)压电衬底与可替换的纳米印迹声波微柱共振膜“贴纸”之间的耦合共振；2)通过单分散金纳米颗粒与检测抗体偶联的均匀银增强实现微米级质量放大器；3)有待开发和训练的机器学习算法，以可靠的方式分析生物传感数据，从而实现更准确的检测。颗粒的数量可以与生物标志物的数量直接相关，实现“数字化”传感。开发的方法不局限于三明治型免疫测定，也不局限于任何特定的蛋白质生物标志物，因此开发的传感器可以推广为监测任何感兴趣的生物分子（如蛋白质生物标志物、病毒和病原体）的通用平台，以确保公共卫生和生物安全。如果成功，这项工作将彻底改变基于声波的生物传感平台。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。

Accurate measurements of proteins are critical for modern biomedical research, particularly for early detection and monitoring of disease, systems biology, and new drug development. More specifically, sensitive, specific, fast, and low-cost detection of proteins biomarkers in patient samples is of importance for public health and a key component of future personalized diagnostics and therapy. To date, enzyme-linked immune-sorbent assays in all their variants are the most common sensing techniques employed to detect the presence of protein biomarkers. However, a number of limitations still exist that greatly diminish their broader applications due to the low-sensitivity, the requirement of a calibration plot to elucidate the results, and the need for advanced costly instruments for ultrasensitive measurement. This proposal aims to address the aforementioned drawbacks by developing a simple and low-cost, but potentially powerful sensor based on the integration of a two-level signal amplification sensing mechanism and machine-learning-enabled reliability. The developed sensing devices are particularly desirable for early disease detection, ideally capable of "digitally" (calibration-free) detecting the presence of biomarkers with excellent portability, adaptability, accuracy, and high throughput. The knowledge and technology gained from this research will be disseminated to the scientific community and industry. This project will impact the education of the graduate, undergraduate and high school students by integrating advanced biosensing knowledge into their educational and laboratory training, and also actively interacting with general public and industry companies.The proposed sensing device will allow immunoassay to be performed as a low-cost and digital (calibration-free) detection technique with potential single copy sensitivity through integration of three key components: 1) a coupled resonance between a piezoelectric substrate and a replaceable nanoimprinted acoustic wave micropillar resonance film "sticker", 2) a micron-sized mass amplifier realized through uniform silver enhancement of mono-dispersed gold nanoparticles conjugated with detection antibody, and 3) machine learning algorithms to be developed and trained to analyze the biosensing data in a reliable way, thus allowing more accurate detection. The number of the particles can be directly correlated to the number of biomarkers, realizing "digital" sensing. The developed methodology is not restricted to sandwich-type immunoassays, nor is the assay limited to any particular protein biomarker and therefore the develop sensor can be generalized as a universal platform for monitoring any biomolecule of interest such as protein biomarkers, viruses, and pathogens for assuring public health and biosafety. The work will revolutionize the acoustic wave-based biosensing platform if successful.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.