NER: Exploratory Research on Developing a Nanoscale Sensing Device for Measuring the Supply of Iron to Eukaryotic Phytoplankton in Natural Seawater

NER：开发纳米级传感装置来测量天然海水中真核浮游植物铁的供应量的探索性研究

• 批准号: 0102334
• 负责人: Mark Wells
• 金额: $ 9.93万
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2003-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0102334&HistoricalAwards=false
• 关键词: NER; Exploratory; Research; Developing; Nanoscale

This proposal was received in response to NSE, NSF-0019.The long delay in recognizing the potentially key role of Fe in coastal marine systems has been in large part because of the complexity of microbial:Fe interactions in seawater. There still is no analytical method for determining biologically available Fe for either prokaryotic or eukaryotic phytoplankton. However, there is evidence that Fe availability to eukaryotic phytoplankton can be regulated by additions of the fungal siderophore desferrioxamine B (DFB) to coastal waters. The DFB-Fe complex not only is unavailable for uptake at significant rates, but also outcompetes the natural organic ligand classes in seawater for Fe. Measurement of DFB-Fe concentrations in a titration series should therefore provide a first order measure of the Fe supply to phytoplankton.This project will investigate the feasibility of miniaturizing a current bulk liquid membrane system that can actively isolate and concentrate 59Fe-DFB from aqueous solutions by constructing liposomes with the needed transport characteristics. The high surface area and optimal diffusional aspects of these nanodevices will enable efficient 59Fe-DFB accumulations at the extremely low dissolved Fe concentrations (1 nM) encountered in coastal waters. The transport characteristics of these nanodevices will be measured as a function of liposome compositions and fabrication conditions to optimize the active transport of 59Fe-DFB from a seawater matrix. If progress permits, the relationship between 59Fe accumulated by these nanodevices and cellular 59Fe uptake and growth of natural population cultures will be explored. The immediate goal of this exploratory project is to demonstrate the feasibility of developing nanoscale sensors for quantifying the supply of Fe to eukaryotic phytoplankton in coastal seawaters. The broader goal is to establish the viability of nanotechnology for sensing bioactive substrates in the marine realm.

这项建议是应NSE，NSF-0019的要求而提出的。在认识到铁在沿海海洋系统中的潜在关键作用方面拖延了很长时间，这在很大程度上是因为海水中微生物与铁的相互作用的复杂性。无论是原核浮游植物还是真核浮游植物，目前还没有一种测定生物有效铁的分析方法。然而，有证据表明，真核浮游植物对铁的有效性可以通过向沿海水域添加真菌铁载体去铁胺B(DFB)来调节。DFB-Fe络合物不仅在很大程度上不能被吸收，而且在海水中对Fe的竞争也超过了天然有机配体类别。因此，滴定系列中DFB-Fe浓度的测量应提供浮游植物铁供应的一级测量。本项目将研究现有的大块液膜系统的可行性，该系统可以通过构建具有所需传输特性的脂质体来从水溶液中主动分离和浓缩59Fe-DFB。这些纳米器件的高表面积和最佳扩散方面将使59Fe-DFB能够在沿海水域遇到的极低溶解铁浓度(1 NM)下高效积累。这些纳米器件的传输特性将作为脂质体组成和制备条件的函数进行测量，以优化59Fe-DFB从海水基质中的主动传输。如果进展允许，将探索这些纳米器件积累的59Fe与细胞内59Fe摄取和自然种群培养生长之间的关系。这一探索性项目的直接目标是证明开发纳米级传感器的可行性，以量化沿海水域中真核浮游植物的铁供应。更广泛的目标是在海洋领域建立用于传感生物活性底物的纳米技术的可行性。