Metalens fluorometer to assess drinking water in Nepal

尼泊尔在饮用水质量方面存在重大问题。评估饮用水质量的工具过于昂贵，而且无法获得。我们将通过开发一种手持式荧光仪来检测色氨酸样荧光作为饮用水中细菌污染的代理来解决这个问题。我们的新颖设计本质上很简单，而且成本很低。该仪器的核心是一个高数值孔径的超透镜，它可以最大限度地提高收集效率，并可以通过纳米压印光刻技术制造。超透镜将被设计成强烈的彩色，这样不同波长的图像就会横向偏移，这样发射器和探测器就可以彼此相邻放置。我们将为在尼泊尔制造、供当地社区使用的原型仪器开发一条翻译途径。

The country of Nepal has major issues with the quality of its drinking water. Tools to assess drinking water quality are too expensive and not available. We will address this problem by developing a handheld fluorometer to detect tryptophan-like fluorescence as a proxy for bacterial contamination in drinking water. Our novel design is intrinsically simple and can be made at low cost. The core of the instrument is a high numerical aperture metalens that maximises collection efficiency and that can be made by nanoimprint lithography. The metalens will be designed to be strongly chromatic such that the images for different wavelengths are laterally displaced, such that emitter and detector can be placed next to one another. We will develop a translation pathway for prototype instruments to be made in Nepal for use in local communities.