Collaborative Research: Changing the manganese paradigm

该项目是特拉华大学和俄勒冈健康与科学大学的研究人员合作的项目，将开发一种灵敏的方法来测量海水中亚纳米摩尔水平的总锰和锰(III)的浓度，无论是在有氧环境中还是在还原区域。该方法是对已有方法的修正，具有NM敏感性。这项为期一年的项目的主要目标是提高该方法的检测下限，并证明其在环境水平(0.5 nm)下测量Mn(III)的能力。将对两种不同的方法进行调查，初步证据表明，这两种方法都是可行的替代方案。使用长光路光学单元将提高当前检测系统的灵敏度，而预浓缩是可以使用的另一种方法。另一种选择是使用荧光检测，这一点也将得到调查。将使用参考材料对各种方法进行测试，包括在最近的海洋学内部校准工作中收集的参考材料。此外，这些方法将在短期巡航和实验室培养实验中进行测试。广泛的影响：锰氧化还原化学影响了一些全球生物地球化学循环，因此了解这些相互作用具有广泛的意义。该项目将培训研究生，并将通过一系列教育和公共宣传活动宣传其成果。这项研究将继续在以前资助的工作中开展的国际合作。

The project, a collaboration between investigators at the University of Delaware and Oregon Health and Science University, will develop a sensitive method for measuring the concentration of total Mn and Mn(III) at sub-nanomolar levels in ocean waters, both in oxic environments and in reduced zones. The proposed method is a modification of a published method, which has nM sensitivity. The improvement in the detection limit of this method and the demonstration of its ability to measure Mn(III) at environmental levels (0.5 nM)is the major goal of this one year project. Two different approaches will be investigated, and preliminary evidence suggests that both approaches are viable alternatives. Use of a long path optical cell will increase sensitivity of the current detection system, and preconcentration is another approach that can be used. An alternative is the use of fluorescence detection, and this will also be investigated. The various methods will be tested using referrence materials, including those collected during recent oceanographic intercalibration exercises. Additionally, the methods will be tested during short cruises and through laboratory culture experiments.Broader Impacts: Manganese redox chemistry impacts a number of global biogeochmeical cycles, and therefore understanding these interactions has broad implications. The project will train graduate students, and the results will be desseminated through a number of educational and public outreach activities. This research will continue international collaborations developed during previously funded work.