Quantum-enabled nano-scale rheology of the microbial seawater environment

尽管外表如此，一滴海水却充满了生命。也许更令人惊讶的是，这种微观生命对海洋和我们的气候都有巨大的影响。浮游植物和细菌等微生物以复杂的方式相互作用，最终决定生产力（食物网底部有多少藻类，导致鱼类种群和渔业的差异）和深海中的碳储存（有助于缓解气候变化）。在过去的几十年里，我们逐渐意识到这些微生物生活在一个不均匀的世界中-也就是说，它们的食物来源和捕食者并不是均匀分布的，即使在100微米（1/10毫米）左右的尺度上也是如此。这种微尺度的斑块是由营养物质和其他化学物质在更小，甚至纳米尺度上移动的方式强烈决定的。我们最近开发了一种新的量子传感方案，当与特定类别的荧光分子结合时，可以在水环境中感测纳米尺度的粘度，因此超越了以前只能在微尺度或非常高的粘度下操作的经典技术。我们的目标是通过优化光子源和用于检测光子对的传感器来进一步改进我们最近对该技术的演示。因此，通过使用一系列尖端的量子传感技术，我们将能够清楚地了解微生物在纳米尺度和微米尺度下的环境。我们将利用新的方法来测量小规模的粘度，微流体设备，现在允许我们在实验室中研究单个微生物和种群的行为反应，以及新的理论来证明这些过程在真实的生活中的存在。我们的目标是巩固量子纳米流变学的一个新领域，然后利用它来揭示小规模粘度差异对海洋微生物之间相互作用的“隐藏”影响，并最终揭示海洋和气候动力学。该项目产生的结果将提高我们对局部地区海洋微生物相互作用的了解，但也将有助于为依赖于微生物生产力准确估计的全球生物地球化学和气候模型提供信息。

Despite appearances, a single drop of seawater is teeming with life. Even more surprising perhaps, is that this microscopic life has a huge influence on both the oceans and our climate. Microorganisms such as phytoplankton and bacteria interact with each other in complex ways that ultimately determine both productivity (how much algae is available at the base of the food web, leading to differences in fish populations and fisheries) and carbon storage in the deep ocean (helping to mitigate climate change). Over the past few decades we have come to realise that these microorganisms live in a world that is patchy - that is their food sources and predators are not spread evenly, even at scales of around 100 micrometres (1/10 of a mm). This microscale patchiness is strongly determined by the way nutrients and other chemicals move at smaller, even nanometric scales.We have recently developed a novel quantum sensing scheme that, when combined with a specific class of fluorescent molecules, can sense nano-scale viscosity in water-environments, therefore outclassing previous classical techniques that can only operate at the micro-scale or at very high viscosities. We aim to further improve our recent demonstration of this technique by optimising the photon sources and also the sensors for the detection of photon pairs.Therefore, by using a range of cutting-edge quantum sensing techniques we will be able to obtain a clear idea of what the nanoscale and microscale environment looks like to a microbe. We will take advantage of new methods to measure viscosity at small scales, microfluidic devices that now allow us to study behavioural responses of individual microbes and of populations in the lab, and novel theory to demonstrate the existence of these processes in real life. Our aim is to consolidate a new field of quantum-enabled nanorheology and to then use this to reveal the 'hidden' impact of small-scale differences in viscosity on the interactions between marine microorganisms and ultimately ocean and climate dynamics. The results generated by this project will improve our understanding of marine microbial interactions in localised areas, but will also help inform global biogeochemical and climate models that rely on accurate estimates of microbial productivity.