Collaborative Research: Infrared Chiral Metasurface Enhanced Vibrational Circular Dichroism Biomolecule Sensing

发展高灵敏度和高选择性的生物分子检测和表征的纳米生物传感技术对于食品安全和营养、生物医学病原体检测、医疗保健、疾病早期诊断和环境监测至关重要。然而，现有的纳米生物传感器面临的主要挑战是以超高的灵敏度区分和识别复杂的手性生物分子，这对快速蛋白质分析、早期疾病检测和实时监测提出了很高的要求。在本项目中，将开发和展示一种新型的红外手性异表面增强生物分子传感平台，用于检测和识别不同类型的蛋白质结构，具有超高检测灵敏度和高信噪比的优点。这项研究将有助于在疾病早期诊断、药物发现、量子传感和远程通信等方面的许多生物医学和光子学应用。该项目还包括培训研究生、招收代表不足的学生和女学生以及在外联计划中指导高中生的教育活动。等离子体纳米生物传感器已被广泛用于生物分子的检测和表征，其传感原理是基于折射率诱导的光谱移动或表面增强的振动吸收。然而，这些纳米生物传感器很难识别生物分子的二级结构，这些二级结构通常具有相似的无特征红外吸收光谱。本项目的目标是研究一种新型的手性异表面增强的振动圆二色谱生物传感平台，用于检测和识别超高检测灵敏度和高信噪比的蛋白质二级结构。基于超手性近场与手性生物分子的振动指纹之间的同共振相互作用，将创造一种新的手性传感范式。在本项目中，将设计和分析各种类型的具有高圆二向色性的中红外手性准表面，用于生物分子传感。将开发纳米制造工艺来制备手性亚表面，并将微流控细胞与蛋白质溶液相结合。手性生物分子传感平台将使用红外手性测量来表征，以展示对蛋白质二级结构的超灵敏识别和检测。该奖项反映了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。

Developing nano-biosensing techniques for the detection and characterization of biomolecules with high sensitivity and selectivity is critically important for food safety and nutrition, biomedical pathogen detection, point-of-care healthcare, early disease diagnostics, and environment monitoring. However, the major challenge for the existing nano-biosensors is to distinguish and identify complex chiral biomolecules with ultrahigh sensitivity, which is highly demanded for rapid protein analysis, early disease detection and real-time monitoring. In this project, a new type of biomolecule sensing platform enhanced by infrared chiral metasurfaces will be developed and demonstrated to detect and identify different types of protein structures, with the advantages of ultrahigh detection sensitivity and high signal-to-noise ratio. This research will benefit many biomedical and photonic applications in early disease diagnosis, pharmaceutical drug discovery, quantum sensing and remote communication. This project also includes educational activities for training graduate students, recruiting underrepresented and female students, and mentoring high school students in outreach programs.Plasmonic nano-biosensors have been widely used for the detection and characterization of biomolecules, where the sensing principle is based on refractive-index induced spectral shift or surface enhanced vibrational absorption. However, it is difficult for these nano-biosensors to identify secondary structures of biomolecules, which usually have similar featureless infrared absorption spectra. The goal of this project is to study a new type of vibrational circular dichroism biosensing platform enhanced by chiral metasurfaces for the detection and identification of protein secondary structures with ultrahigh detection sensitivity and high signal-to-noise ratio. A new chiroptical sensing paradigm will be created relying on the on-resonance interactions between the superchiral near-fields and the vibrational fingerprints of chiral biomolecules. In this project, various types of mid-infrared chiral metasurfaces with high circular dichroism will be designed and analyzed for biomolecule sensing. Nanofabrication processes will be developed to fabricate chiral metasurfaces and integrate the microfluidic cells with protein solutions. The chiral biomolecule sensing platform will be characterized using infrared chiroptical measurements to demonstrate the ultrasensitive identification and detection of protein secondary structures.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.