IDBR: Development of a device to improve accuracy and reduce variability of in situ fluorometric measurements in aquatic environments

威斯康星大学密尔沃基分校被授予一项奖项，以开发一种新设备，改进对水环境中藻类色素的自动监测。监测湖泊、河流和海洋中的藻类色素，如叶绿素和藻蓝蛋白的能力，对于我们理解水生生态系统和藻类生态是至关重要的。自主的原位荧光传感器允许在高分辨率的时间尺度(几分钟到几小时)连续测量这些颜料。这些传感器提高了我们对在次日时间尺度和昼夜循环中发生的过程的理解。目前，至少有两个主要的混杂变量使这种传感器数据的解释变得复杂。每单位色素的荧光产量因藻类光照历史的不同而变化几个数量级，因为暴露在光下的细胞产生的每种色素分子的荧光产量较低。此外，由于藻细胞在群体或颗粒中的不均匀分布，传感器信号的极端变异性(即从检测极限到传感器饱和)发生。目前还没有可用的技术来解决这些问题。将设计、制造和测试一种设备，以显著减少这些令人困惑的变量。“色素孵化研磨室”，或CPIG，自动对一等分的水进行采样，将其在黑暗中保持一段预定的时间，以便对曝光的藻类颜料进行黑暗恢复，并在使用商用荧光传感器进行荧光测量之前将样品均质。该设备可接受各种现场荧光仪，可通过USB输入完全编程，并可与全球连续监测站使用的典型数据记录器/调制解调器设置接口。它是鞋盒大小，小到足以安装在数据浮标上或固定的监测站，电力需求低。现场荧光计被世界各地从事水质监测的数千名科学家和资源管理人员使用。它们有可能减少耗时的人工水样和昂贵的藻类色素实验室分析。CPIG将大大减少影响现场荧光测量的两个最大的混杂变量，使其在全球数千个水质监测点得到更广泛的应用。该项目通过支持研究生论文研究项目来推进科学教育，并聘请来自代表性不足群体的本科生研究员，包括即将入学的新生和麦克奈尔学者。该设备的数据将部署在美国和国际上的监测站，为各种利益相关者提供监测数据。此外，该设备将被引入全球湖泊生态观测站(GLEON)网络，这是一个由数百名科学家和学生组成的草根国际组织，使用和管理部署在世界各地湖泊的现场传感器。CPIG测试产生的所有数据将立即通过GLEON在线数据库免费提供。该项目涉及到威斯康星大学商学院市场营销专业的本科生，涉及多个学科。这些学生将为CPIG设计营销计划，以便向更大的科学界宣传和传播该设备，同时了解营销科学仪器的挑战。由生物基础设施部的生物研究仪器开发(IDBR)计划资助。

An award has been made to the University of Wisconsin-Milwaukee to develop a new device that improves automated monitoring of algal pigments in aquatic environments. The ability to monitor algal pigments such as chlorophyll and phycocyanin in lakes, rivers, and oceans is central to our understanding of aquatic ecosystems and algal ecology. Autonomous in situ fluorometric sensors allow these pigments to be measured at highly resolved timescales (minutes to hours) on a continuous basis. These sensors have advanced our understanding of processes that occur at subdaily timescales and on day/night cycles. Currently the interpretation of this sensor data is complicated by at least two major confounding variables. Fluorescent yield per unit of pigment varies by orders of magnitude due to algal light history since light exposed cells produce a lower fluorescent yield per pigment molecule. In addition, extreme variability in sensor signals (i.e. from detection limits to sensor saturation)occurs due to the heterogeneous distribution of algal cells in colonies or particles. No technology currently available addresses these issues. A device will be designed, built, and tested that significantly reduces these confounding variables. The "Chamber for Pigment Incubation and Grinding," or CPIG autonomously samples an aliquot of water, holds it in the dark for a predetermined period of time allowing for dark recovery of light exposed algal pigments and homogenizes the sample before taking fluorescent measurements using commercially available fluorometric sensors. The device accepts a variety of in situ fluorometers, is completely programmable via USB input and can interface with typical data logger/modem setups used at continuous monitoring stations globally. It is shoeboxed sized, small enough for installation on data buoys or at fixed monitoring stations and has low power requirements.In situ fluorometers are used by thousands of scientists and resource managers around the world engaged in water quality monitoring. They have the potential to reduce time-­consuming manual water sampling and costly laboratory analyses of algal pigments. The CPIG will significantly reduce two of the largest confounding variables affecting in situ fluorometric measurements making them more widely applicable at thousands of water quality monitoring sites across the globe. The project advances science education by supporting a graduate dissertation research project and engages undergraduate research fellows from underrepresented groups, including incoming freshmen and McNair Scholars. Data from the device will be deployed at monitoring stations in the U.S. and internationally, providing monitoring data for a variety of stakeholders. Furthermore, the device will be introduced to the Global Lakes Ecological Observatory (GLEON) network, a grass roots international organization composed of hundreds of scientists and students using and managing in situ sensors deployed in lakes around the world. All data produced by the CPIG testing will be immediately available for free via GLEON online databases. This project crosses disciplines as it engages undergraduate students enrolled in a marketing course within the UWM School of Business. These students will design a marketing plan for the CPIG in order to advertise, and disseminate the device to the larger scientific community while simultaneously learning about challenges in marketing scientific instruments.Funded by the Instrument Development for Biological Research (IDBR) program in the Division of Biological Infrastructure.