PFI-TT: Achieving efficient production of visible light from semiconductor nanocrystals in water

该创新技术转化伙伴关系（PFI-TT）项目具有更广泛的影响/商业潜力，是一种基于纳米晶体的光吸收剂，可在生物友好的水性介质中将近红外（NIR）转换为可见光。该项目解决了生命科学中未满足的需求，因为目前不可能在没有手术或使用超过哺乳动物疼痛阈值的非常强的激光的情况下，将紫光深入活体哺乳动物体内。该项目将推进原型系统的开发。在皮肤以下几厘米处无创地传递紫光的能力将促进检测氧气（缺氧）的新方法，并为即时诊断（POC）创造廉价的光源。潜在的商业应用包括绘制神经网络，减轻疼痛，人为控制昼夜节律，减轻抑郁，以及临床前研究中的生理过程成像。除了对这些庞大且不断增长的数十亿美元市场产生影响外，这项创新还将为神经科学、光片成像和昼夜节律研究等不同学术领域带来新的方向。该项目将建立稳定水中疏水纳米晶体和分子天线的新方法。目标是在水介质中实现最先进的光子上转换量子产率，而不是以前在有机溶剂中的记录。研究目标包括建立一个动力学或热力学屏障，将半导体纳米晶体和分子发射体与水环境隔离开来，同时防止被环境氧猝灭。本文提出的纳米或微囊泡或乳液将通过微调各种成分的相对比例及其不同的溶解度来稳定。高光子上转换量子产率所必需的自旋三重态激发态将被化学屏障或添加剂保护以防止氧的意外猝灭。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。

The broader impact/commercial potential of this Partnerships for Innovation - Technology Translation (PFI-TT) project is a nanocrystal-based light absorber that converts near infrared (NIR) to visible light in biologically friendly aqueous media. This project addresses unmet needs in the life sciences where the deep targeted delivery of light to tissue is needed because it is currently impossible deliver violet light deep inside living mammals without surgery or using a very intense laser that exceeds the mammalian pain threshold. This project will advance the development of a prototype system. The ability to deliver violet light non-invasively centimeters below the skin will facilitate new ways to detect oxygen (hypoxia) and create inexpensive light sources for point-of-care (POC) diagnostics. Potential commercial applications include mapping neural networks, mitigating pain, artificially controlling the circadian rhythm, alleviating depression, and imaging physiological processes in preclinical research. Apart from impact in these large and growing billion-dollar markets, this innovation will enable new directions in the diverse academic fields of neuroscience, light-sheet imaging and circadian rhythm research. The proposed project will establish novel methods for stabilizing hydrophobic nanocrystals and molecular antennas in water. The goals are to realize state-of-the art photon upconversion quantum yields with this hybrid platform in aqueous media, as opposed to previous records in organic solvent. Research objectives include establishing a kinetic or thermodynamic barrier that isolates the semiconductor nanocrystals and molecular emitters from their aqueous surroundings while preventing quenching by ambient oxygen. The nano- or micro-vesicles or emulsions proposed here will be stabilized by fine-tuning the relative ratios of various components and their differing solubilities. The spin-triplet excited state necessary for high photon upconversion quantum yields will be protected against undesired quenching by oxygen with chemical barriers or additives.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.