Name: an ultra-clean multilayer apparatus for collecting size fractionated marine plankton and suspended particles
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作者感谢皮分林小姐、魏隆先生、裴小姐和佳禄博士在实地抽样和实验室分析中对 "CATNET" 的实际开发和应用进行了协助。在取样远征期间, 船员和技术员对船上研究船海洋研究和海洋研究 II 的协助非常感谢。这项工作部分是由台湾科学技术部资助的91-2611 米-002-007、95-2611 米-002-009、96-2611 米-002-004、97-3114 米-002-006、104-2611 米-002-019。这篇手稿是为了纪念翬小姐对台湾海洋研究的巨大奉献和贡献而写的。

以下议定书涉及使用有害化学品。请仔细阅读安全数据表 (SDS), 并遵循机构化学安全指南。
1. 多层重力过滤取样器的制备
<ol><li>
取样器清洗
	<ol>
<li>用 1% (w/v) 的阴离子蛋白酶酶洗涤剂溶液填充油管和过滤单元, 浸泡24小时, 用反渗透双蒸馏水 (RO-DDW) 彻底冲洗多层重力过滤取样器, 然后将其填充 0.1% (v/v)盐酸 (盐酸, 试剂级) 和浸泡72小时。</li>
		<li>用反渗透双蒸馏去离子水 (RO-DIW) 将多层重力过滤取样器彻底冲洗三至五次, 每次至少20公升, 并将组合存放在塑料袋中。</li>
	</ol>
</li>
	<li>
微粒样品容器清洁/准备
	<ol>
<li>使用低密度聚乙烯 (聚乙烯, 125 毫升) 或氟化乙烯丙烯 (FEP, 125 毫升) 瓶作为容器的微粒。先用碱性洗涤剂 (微, 1%), 然后在 50% (v/v) 硝酸 (HNO3, 试剂级), 然后 10% (v/v) HCl 溶液的至少 24, 48 和 24 h, 清洗瓶子, 分别。在两个浸泡步骤之间用脱电离水 (RO-DIW) 冲洗瓶子。</li>
		<li>在最后的 HCl 浸泡后, 彻底冲洗瓶子与脱电离水 (RO-DIW), 并干燥的瓶子在一个干净的房间或 class-100 干净的长凳。 将清洗过的瓶子连接到多层重力过滤取样器, 或将清洗过的瓶子密封在 PE 拉链袋中, 并用双袋包装运输。</li>
	</ol>
</li>
	<li>
多层重力过滤取样器的组合
	<ol>
<li>将六4米长的耐化学热塑性弹性体管 (外径0.635 厘米) 连接到取样器顶部的六方向入口。</li>
		<li>将三种不同的网状尼龙过滤器与低密度聚乙烯样品容器 (125 毫升聚乙烯) 依次组装在洁净室 (工作台) 清洗后 (见下文), 用10µm 网格过滤器定位在外部, 63 µm 网格过滤器在中间, 和153µm 网格过滤器在里面。运输时, 将多层重力过滤取样器存储在两层聚乙烯 (PE) 袋中, 然后放入聚丙烯 (PP) 装运容器中。</li>
	</ol>
</li>
</ol>2. 取样
<ol><li>
示例集合
	<ol>
<li>抵达取样地点后, 有一人从研究船甲板上的装运集装箱中取出多层重力过滤取样器, 并用取样装置打开袋子。然后, 让他们穿上 PE 手套, 将六4米热塑性弹性体管连接到高架多瓶取样阵列上的六 20 L 聚四氟乙烯涂层取样瓶的水闸门, 并将海水引导到这个过滤单元中。海水将流经定向入口, 粒子/浮游生物将被轻轻地分离/分割通过网, 并落户到125毫升的低密度聚乙烯瓶, 在网底固定。</li>
		<li>海水流经后 (通常为120升为沿海海水, 240 升为开阔海水), 按顺序去除每个网 (首先, 153 µm, 然后63µm, 最后10µm) 在一个 class-100 干净的工作台, 然后喷洒净与微量金属清洁0.4 µm filtered 海水冲洗出网内表面的任何浮游生物。在125毫升聚乙烯瓶中收集浓缩颗粒/浮游生物的海水。</li>
		<li>将这些瓶子从网中拧开, 再通过酸性洗涤的真空过滤装置, 在低真空下用预称量、酸洗47毫米、10µm 孔径聚碳酸酯过滤器过滤溶液。条件 (< 5 帕)。</li>
		<li>要收集小于10µm 的微粒/浮游生物, 请等待至少20升的海水流经取样器, 然后在 5 L PE 容器中收集两到五升的水, 然后用酸性洗涤的真空过滤装置过滤这些水样, 并预重, 酸性水洗, 47 毫米, 0.4 µm 孔径聚碳酸酯过滤器。</li>
		<li>真空过滤后, 立即用高纯度的 DDW 水冲洗样品过滤器, 去除海水中的残留物, 尽量减少海水盐分对测定颗粒/浮游生物干重的影响。保持冲洗量只有几毫升, 以防止破坏脆弱的浮游生物。</li>
		<li>然后, 在此冲洗步骤后, 小心地将过滤器从真空过滤单元中取出, 将样品过滤器储存在酸洗、预压丙烯酸塑料培养皿中, 并密封在密封塑料袋中。把袋子放在-20 ˚C 的冰箱里, 直到回到陆地实验室进行进一步的样品预处理和化学分析。</li>
	</ol>
</li>
</ol>3. 样品处理
<ol><li>
颗粒的冷冻干燥和消化
	<ol>
<li>将过滤器与颗粒样品放在冷冻干燥机的收集室中, 并打开机器。当机器温度达到-40 摄氏度时, 打开机器的真空泵, 开始冷冻干燥过程。 注: 真空度应保持稳定在0.12 毫巴以下。请仔细阅读用户手册, 并按照制造商的指导方针为每个步骤。</li>
		<li>72小时后, 关闭冷冻干燥机, 取出干燥过滤器并称重。然后, 将干样过滤器放入预称量的 perfluoroalkoxy 烷烃 (粉煤灰) 容器 (60 毫升容量), 并将3毫升浓缩的超纯硝酸加入容器中2,3,6,7。</li>
		<li>用扭矩扳手将容器拧紧至2.5 公斤的恒定扭矩, 并将容器放在一个常规烤箱中, 在130摄氏度为12小时, 用于第一消化序列。冷却后, 从烤箱中取出容器, 打开容器, 将2毫升的超纯氢氟酸加入容器中2,3,6,7。</li>
		<li>拧紧的扭矩为2.5 公斤的船只, 并把这些船只在一个传统的烤箱在130°c 12 小时, 这是第二消化序列。冷却后, 打开容器, 并将16毫升4.5% 超纯硼酸溶液添加到容器中2,3,6,7。</li>
		<li>将容器拧紧至2.5 公斤米的恒定扭矩, 并在烤箱中以130°c 的样品消化, 最后消化顺序为12小时。冷却后, 权衡每一个容器, 并确定每一个消化溶液的最终质量和特定质量, 以产生最终的配药体积。 注意: 具体质量是通过测量准确的1.00 毫升配药的重量来确定的。</li>
		<li>小心倒入30毫升酸清洗 PE 瓶配药进一步的微量金属分析。</li>
	</ol>
</li>
	<li>
微量金属分析
	<ol>
<li>用石墨炉原子吸收光谱仪 (GF-原子吸收光谱法)6测定颗粒的消化溶液中的微量金属浓度 (镉、铜、铁、锰、镍和铝)。</li>
		<li>作为精度测试, 使用经认证的参考材料 (CRM), 如加拿大国家研究委员会的海洋沉积物参考材料, 河口泥沙标准参考材料从国家标准和技术研究所美国和浮游生物参考材料从欧洲委员会的科学和知识服务。该过程使 CRM 中提供的微量金属的认证价值得到95% 到107% 的恢复。</li>
	</ol>
</li>
</ol>

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合著者艾伦. 创先生是该公司的专利共同所有者和总经理 (中信仪器有限公司), 为感兴趣的用户制造了这个收集设备。该专利于 5月9日 (th, 201512) 结束。

获得可靠的微量金属浓度的浮游生物和悬浮粒子在自然水域, 通常是在非常低浓度, 需要很大的照顾, 在样品收集, 处理, 预处理和分析, 目的是减少污染。因此, 设计和准备取样齿轮、样品容器和用于收集和处理样品的材料的程序是在海洋环境中获得高质量的微量金属数据的关键步骤。随着近几十年来新的粒子采集方法的发展, 我们对粒子动力学和微量元素地球化学的认识也在不断拓宽。本文介绍了一种可用于研究海洋浮游生物/粒子的分布和组成的序贯大小分馏技术。在我们调查的海水中, 微量金属的成分在不同大小和起源的粒子上有显著的变化, 超过五级。一般情况下, 大多数小颗粒 (0.4-10 µm) 富含微量金属, 如 Fe 和铝, 浓度随着大小的增加而降低3,10,14。与常规的死端过滤相比, 沿海海水中总颗粒浓度的结果表明, 使用该方法得到了良好的一致性。
此处所述的议定书可以很容易地用于收集不同类型的海洋环境、河口和沿海水域、湖泊或开阔海洋。样品体积可以调整, 如果需要更大或更少的粒子量。在高度浑浊的水域中, 样品仍应清理干净, 在处理下一次水样之前, 必须非常小心地清除附着在尼龙网上的残余微粒。清洗和预适应步骤, 以及对 "微量金属取样清洁技术" 的认识对于满意的质量平衡和持续良好的效果是至关重要的。这项研究表明, 海洋浮游生物和悬浮粒子中微量金属分布的测定需要 "清洁技术", 包括取样和分离, 这种装置和相关的处理结果得到了改进。
本议定书适用的大体积海水的范围意味着在各种海洋环境中也可以有效地进行颗粒分布和行为的调查。在离散样品中, 粒子的收集和化学表征仍然有空间和时间的限制, 这可能会引入偏差的解释由于可能不完整的粒子场的帐户。然而, 通过比较各种粒子收集方法的结果, 我们可以进一步扩大粒子/浮游生物的研究范围, 提供有关不同粒径的反应和过程的细节, 并确定其相应的生物地球化学动力学。对粒子/浮游生物的持续研究将揭示它们在海洋中的作用。

海洋中的粒子在海洋生物地球化学循环中起着重要作用1。粒子的大部分属性, 如大小、矿物学和组成, 都可以从一个地质或水文设置到另一个2。此外, 海洋中元素的分布也与海洋浮游植物的生命周期有关: 生长、死亡、下沉和再矿化3,4。海洋颗粒的大小至少有4级, 从亚微米颗粒到大骨料 (> 5 毫米) 不等。大多数粒子都是从生物学上衍生出来的, 从病毒裂解、渗出、分泌、粪便颗粒的产生、等等。其他粒子是由细胞、细胞碎片或胆汁成石材料的物理凝固而形成的1。微粒的各种各样的化学和生物特征控制地球化学循环和生物过程发生在和在微粒之内4,5,6。这些微粒是重要栖所和食物来源为一些有机体, 例如浮游动物或 saprotrophs。因此, 粒子的命运常常与它们的大小有关, 而粒子的生物过程可以改变它们的尺寸。
取样海洋微粒通常需要过滤, 但这种方法在识别粒子的性质方面引入了一定的模糊性, 因为海洋颗粒在成分和大小上不均匀。悬浮粒子, 主要由几乎永久悬浮的小颗粒和低密度粒子组成, 在悬浮液中, 由于水动力条件, 在短时间内混合了不同数量的大颗粒和高密度粒子。7. 在研究船8上, 通过浮游生物拖曳或悬浮浮游生物网收集浮游生物样品的微量金属组成的第一个报告。作者经常在样品中发现金属微粒和油漆芯片, 这表明在化学分析中, 海洋微粒取样过程中存在严重的污染问题。其他努力包括用橡皮筏进行净拖曳或使用聚氯乙烯 (PVC) 手绞车3。对粒子进行可靠取样的困难使得我们对海洋粒子化学成分的理解更加困难, 特别是对于微量元素。因此, 关于浮游植物中微量元素浓度的最关键信息来自于文化研究9,10。这一认识促使海洋科学家在过去三十年中为研究海洋中的粒子创造了新的方法11。
海洋学家使用了各种取样技术, 包括船用过滤、原位过滤和沉积陷阱11。处理大量的海水来收集无污染的样品可能是一个挑战, 特别是对于开阔的海洋和深水域, 其中颗粒浓度非常低 (0.001-0.1 毫克/升)。还需要过滤大量的海水, 以获得足够数量的微粒来测量微量金属浓度。一些研究人员使用了粒度分馏法将悬浮粒子与下沉粒子分离。然而, 颗粒的大小、孔隙度、密度和形状都能影响颗粒的下沉速度。沉淀物陷阱不是收集悬浮粒子的实用工具, 因为这些是为下沉粒子设计的。因此, 有必要制定取样和处理方法, 以便收集足够数量的悬浮粒子, 并将其污染降到最低。因此, 在海洋学家的取样工具箱中, 通过原位过滤来进行尺寸分割仍然是一个有希望的工具, 因为它可以揭示海洋粒子动力学的关键信息。在这里, 我们描述了一个成功测试的微量金属清洁, 多层重力过滤取样装置, 它可以处理大容量 (120-240 升) 的船上的海水在一个通行证从聚四氟乙烯 (聚四氟乙烯) 涂层水取样瓶在一个多瓶取样阵列。该取样装置采用酸性水洗合成尼龙网, 并将网套在聚碳酸酯容器内, 以轻轻收集大小分级悬浮物质和浮游植物12,13, 14,15 (图 1)。这项工作的目的是提供一个更好的工具, 以研究在海洋环境中的金属粒子协会及其反应动力学, 并提高我们对各种浮游生物, 粒子和微量金属的命运的理解, 在这些环境。

<table><tbody><tr><td>thermoplastic elastomer (C-Flex) Tubings</td><td>Cole Palmer</td><td>EW-06424-67</td><td>O.D. 0.635 cm, Opaque White 1/8&quot;ID x 1/4&quot;OD, 25 ft/pack</td></tr><tr><td>LDPE Bottle (Nalgene)</td><td>ThermoFisher Scientific</td><td>2103-0004</td><td>125 mL, Nalgene Wide-Mouth LDPE Bottles with Closure</td></tr><tr><td>anionic protease enzyme detergent detergent (Tergazyme)</td><td>Alconox</td><td>1104-1</td><td>1&amp;times;4 lb box (1.8 kg)</td></tr><tr><td>Hydrochloric Acid</td><td>Sigma-Aldrich</td><td>258148</td><td>Reagent grade</td></tr><tr><td>Nitric acid</td><td>Sigma-Aldrich</td><td>695025</td><td>Reagent grade</td></tr><tr><td>alkaline detergnet (Micro)</td><td>Cole Palmer</td><td>EW-99999-14</td><td>Micro-90 Cleaning Solution</td></tr><tr><td>polycarbonate filter, 47 mm, 0.4 &amp;micro;m</td><td>Sigma-Aldrich</td><td>WHA111107</td><td>Whatman Nuclepore Track-Etched Membranes, diam. 47 mm, pore size 0.4 &amp;mu;m, polycarbonate</td></tr><tr><td>polycarbonate filter, 47 mm, 10 &amp;micro;m</td><td>Sigma-Aldrich</td><td>WHA111115</td><td>Whatman Nuclepore Track-Etched Membranes, diam. 47 mm, pore size 10 &amp;mu;m, polycarbonate</td></tr><tr><td>PFA vessel, 60 ml capacity</td><td>Savillex</td><td>300-060-03</td><td>60 mL Digestion Vessel, Flat Interior, Flat Exterior, Buttress Threaded Top</td></tr><tr><td>Nitric acid, ultrapure</td><td>Seastar Chemicals</td><td>N/A</td><td>BASELINE Nitric Acid</td></tr><tr><td>HF, ultrapure</td><td>Seastar Chemicals</td><td>N/A</td><td>BASELINE Hydrofluoric Acid</td></tr><tr><td>Boric acid, ultrapure</td><td>Seastar Chemicals</td><td>N/A</td><td>BASELINE Hydrobromic Acid</td></tr><tr><td>polyethylene (PE) gloves</td><td>Safty Zone</td><td>GDPL-MD-5</td><td>Clear Powder Free Polyethylene Gloves</td></tr><tr><td>Multiple layer filtering and collecting device</td><td>Sino Instrumnets Co. Ltd</td><td>not available</td><td>Multiple layer filtering and collecting device, CATNET</td></tr><tr><td>10 um Nylon filters, Nitex</td><td>Dynamic Aqua-Supply Ltd.</td><td>NTX 10</td><td>Nitex - Standard Widths (40 - 44 inches)</td></tr><tr><td>60 um Nylon filters, Nitex</td><td>Dynamic Aqua-Supply Ltd.</td><td>NTX 60</td><td>Nitex - Standard Widths (40 - 44 inches)</td></tr><tr><td>150 um Nylon filters, Nitex</td><td>Dynamic Aqua-Supply Ltd.</td><td>NTX 150</td><td>Nitex - Standard Widths (40 - 44 inches)</td></tr><tr><td>torque wrench</td><td>Halfords</td><td>200238</td><td>Halfords Professional Torque Wrench 8-60Nm</td></tr><tr><td>multi-bottle sampling array, Rosette</td><td>General Oceanics</td><td>Model 1018</td><td>Rosette Sampler</td></tr><tr><td>PTFE-coated sampling bottles, GO-Flo</td><td>General Oceanics</td><td>108020T</td><td>GO-Flo water sampler teflon coated</td></tr><tr><td>Marine sediment reference materials</td><td>National Research Council Canada</td><td>MESS-3</td><td></td></tr><tr><td>Estuarine sediment standard reference material</td><td>National Institute of Standards and Technology</td><td>1646a</td><td></td></tr><tr><td>Plankton reference material</td><td>The European Commission&#039;s science and knowledge service</td><td>CRM414</td><td></td></tr></tbody></table>

an ultra-clean multilayer apparatus for collecting size fractionated marine plankton and suspended particles

海洋中许多微量元素的分布与海洋浮游生物的生长、死亡和再矿化以及悬浮/下沉粒子的沉积密切相关。在这里, 我们提出了一个全塑料 (聚丙烯和聚碳酸酯), 多层过滤系统收集悬浮微粒物质 (SPM) 在海上。这种超清洁取样装置是专门为微量元素研究而设计和开发的。对所有非金属材料进行细致的选择, 并利用在线流动过程, 最大限度地减少取样过程中可能发生的金属污染。该系统已成功测试和调整, 以确定痕量金属 (如, 铁, 铝, 锰, 镉, 铜, 镍) 对不同大小的颗粒在沿海和开阔海域。东南亚时间序列 (座位) 站南中国海的结果表明, 透光地区浮游生物的日变化和空间分布可以很容易地得到解决和识别。台湾海峡地表水中颗粒粒度的化学分析表明, 较大的颗粒 (> 153 µm) 主要是生物衍生的, 而较小的颗粒 (10-63 µm) 主要由无机物质组成。除 Cd 外, 金属 (铁、铝、锰、铜、镍) 的浓度随尺寸的增大而减小。

随着现代海洋学的发展, 使用 "清洁技术" 获得准确的海洋颗粒或浮游生物中微量金属浓度是目前的普遍做法。由于天然水体中的大多数粒子都处于低镁/升到µg 的范围内, 因此必须对大量海水进行处理, 以调查在环境环境中微量金属对各种粒子的地球化学和生物效应。使用清洁、多层重力过滤 ("CATNET") 取样技术 (图 1), 在确定使用常规加压死端过滤和 CATNET 收集的粒子浓度之间找到了很好的协议,使用从台湾西海岸取样的沿海海水数据集 (图 2)。这些微粒中有90% 以上是小的 (0.4-10 µm)。当将环境未过滤海水与 CATNET 过滤海水 (< 10 µm) 进行比较时, 使用此协议可产生非常低的空白, 并且没有明显的污染 (表 1)。对于收集在叶绿素深度的粒子-最大值在南中国海在 3/26/2002 和 3/28/2002 之间, 多数微粒 (> 80%) 居住在更小的 (0.4-10 µm) 微粒。较大的粒子,即, 浮游动物 (> 153 µm), 清楚地显示了日垂直迁移模式, 而较小粒子的浓度保持几乎不变 (图 3)。在取样瓶中观察到的活浮游动物表明过滤过程的温和性为10。在台湾海峡的地表水中, 本文描述的分析湿化学和取样技术用于测量海洋颗粒的分布和组成。在所收集的不同大小分数中, 悬浮粒子 (µg/g) 中平均金属浓度的直方图变化显著, 超过五级。不同粒径组的浓度差异显著: 0.4-10 µm、10-63 µm、63-153 µm 和 > 153 µm。一般情况下, 大多数颗粒在铁和铝中富集, 浓度随尺寸的增大而减小, 而 Cd 除外, 随着尺寸的增加而增加, 可能是由生物浓度过程3,10, 14 (图 4)。
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/56811/56811fig1.jpg"> 图 1: 超清洁多层重力过滤取样器, 用于收集大小的海洋浮游生物和悬浮粒子 (CATNET).该粒子收集取样器是由聚碳酸酯和聚丙烯材料, 并按顺序安装, 与153µm, 63 µm, 10 µm 可变尼龙网。水样由六20升聚四氟乙烯涂层取样瓶在高架多瓶取样阵列上抽取, 通过酸性水洗热塑性弹性体管连接到尺寸分级过滤装置的流入端。这种过滤系统有效地防止了在船上采集样品时可能发生的污染, 粒子通过网的顺序轻轻地分开, 在每个网底的低密度聚乙烯瓶子里下沉。"CATNET" 是由合著者翬李小姐的绰号, 简称 "猫博士的超清洁多层收集网", 使用户可以区分设备和过滤方法的设计师/发明家, 梁博士锯"猫" 文。此设备已获得专利, 直到 5月9日th, 201512。<a href="https://cloudflare.jove.com/files/ftp_upload/56811/56811fig1large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/56811/56811fig2.jpg"> 图 2: 通过两种独立的过滤方法比较从沿海水域收集的总悬浮材料 (TSM).2007年4月在 R/V 海洋研究 II 上收集了5米深度的沿海水样 (OR2-1432、2007/4/21-4/23)。(a) 取样站 (b) 取样程序示意图 (c) 由 CATNET 方法确定的每个样本点的不同粒度粒子浓度, (d) 测定的颗粒浓度比较常规过滤方法 (TSM) 和 CATNET 法 (TTSM)。误差线是由 TSM 测量的重复样本的标准偏差。在相同样品的分离整除数中, 用两种独立的方法确定悬浮粒子浓度之间存在很好的一致性。共有22个取样点, 每个站点的两个样本由常用的、加压的死端过滤装置7、11、16 (总悬浮材料、"TSM") 直接收集和过滤,颗粒重量大于0.4 µm), 另一样品由 CATNET 收集, 其次是低压真空过滤 (总数量的悬浮材料, "TTSM", 重量的总和 0.4-10, 10-63, 63-153 和 > 153 µm 微粒; 只做一次由于操作时间)。一个大的浓度范围意味着这些技术是适合的粒子研究在不同的环境中浓度显示显著差异。<a href="https://cloudflare.jove.com/files/ftp_upload/56811/56811fig2large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always"><tbody>
<tr>
<td>样本</td>
			<td>场双去离子水空白</td>
			<td>
环境海水 (< 0.4 µm)
</td>
			<td>
CATNET 滤液海水 (< 10 µm)
</td>
		</tr>
<tr>
<td>亚硝酸盐 (µM)</td>
			<td>北达科他州</td>
			<td>0.23</td>
			<td>0.22</td>
		</tr>
<tr>
<td>硝酸盐 (µM)</td>
			<td>北达科他州</td>
			<td>1。4</td>
			<td>1.45</td>
		</tr>
<tr>
<td>铵 (µM)</td>
			<td>北达科他州</td>
			<td>0.081</td>
			<td>0.088</td>
		</tr>
<tr>
<td>磷酸盐 (µM)</td>
			<td>北达科他州</td>
			<td>0.16</td>
			<td>0.15</td>
		</tr>
<tr>
<td>硅酸盐 (µM)</td>
			<td>北达科他州</td>
			<td>4.01</td>
			<td>4.05</td>
		</tr>
<tr>
<td>DOC (µM)</td>
			<td>北达科他州</td>
			<td>83</td>
			<td>81</td>
		</tr>
<tr>
<td>铜 (nM)</td>
			<td>0.08</td>
			<td>0.91</td>
			<td>0.85</td>
		</tr>
<tr>
<td>Fe (nM)</td>
			<td>0.005</td>
			<td>0.34</td>
			<td>0.35</td>
		</tr>
<tr>
<td>镍 (nM)</td>
			<td>0.01</td>
			<td>2.45</td>
			<td>2.35</td>
		</tr>
</tbody></table>表 1: 在程序空白水域、环境海水和 CATNET 过滤水域中的养分和微量金属浓度.在3场空白 (在田间作为样品处理的高纯度水) 和环境水 (115˚34 ' E, 18˚15 ' N; 80 米深度) 的营养和微量金属浓度的说明在 CATNET 过滤前后, 表明其有效性描述的协议。没有证据显示由于限制应力效应 (由于碰撞、不自然的光暴露、温度冲击、剧烈的混合、细胞破裂、等) 或污染 (微量金属在洗涤和收集瓶, 收集齿轮, 配件和电线, 塑料关闭,等)。还实现了低场空白。无法检测: 北达科他州
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/56811/56811fig3.jpg"> 图 3: (a) 透光区叶绿素荧光的时间变化, (b) 在叶绿素深度处收集的不同大小的粒子-最大值.2002年3月在 R/V 海洋研究 I 上收集了样本 (OR1-639, 2002/3/21-3/30)13。在 (a) 中有三角形的虚线表示了该转换的向下和水文数据检索时间;实心三角形表示 CATNET 部署中叶绿素最大深度的粒子的取样时间。虽然一些较小的粒子浓度保持几乎不变, 浮游动物 (> 153 µm) 清楚地显示夜间垂直迁移模式。<a href="https://cloudflare.jove.com/files/ftp_upload/56811/56811fig3large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/56811/56811fig4.jpg"> 图 4: 在不同大小的干燥悬浮粒子 (µg/克) 中平均金属浓度的比较.(a) 2007年夏季在 R/V 海洋研究 II 上收集了样本 (OR2-1444, 2007/5/31-6/6)。(b) 所有35个样本在不同大小之间的平均金属浓度与干悬浮粒子 (µg/克) 的标准偏差。总的来说, 痕量金属成分变化显著, 超过五级的数量。在台湾海峡地表水中, 微量金属浓度在不同大小的微粒 (0.4-10、10-63、63-153 和 > 153 µm) 上也有显著差异;一般而言, 除 Cd 外, 浓度随尺寸的增大而减小.<a href="https://cloudflare.jove.com/files/ftp_upload/56811/56811fig4large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>

Watch this Scientific Journal Video about An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles at JoVE.com

An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles

海洋浮游生物和悬浮颗粒的超洁净多层采集装置

浮游生物和悬浮粒子在海洋生物地球化学循环中起着重要作用。在这里, 我们提供了一种超清洁, 低应力的方法, 以收集各种大小的颗粒和浮游生物在海上的能力, 处理大量的海水。

The distributions of many trace elements in the ocean are strongly associated with the growth, death, and re-mineralization of marine plankton and those ...

an-ultra-clean-multilayer-apparatus-for-collecting-size-fractionated

Nanyang Technological University

Research

JoVE Journal

Environment

8.8K 次观看.  National Taiwan University. 浮游生物和悬浮粒子在海洋生物地球化学循环中起着重要作用。在这里, 我们提供了一种超清洁, 低应力的方法, 以收集各种大小的颗粒和浮游生物在海上的能力, 处理大量的海水。

视频: An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles

Unraveling the Unseen Players in the Ocean - A Field Guide to Water Chemistry and Marine Microbiology

Here we introduce a series of thoroughly tested and well standardized research protocols adapted for use in remote marine environments. The sampling protocols include the assessment of resources available to the microbial community (dissolved organic carbon, particulate organic matter, inorganic nutrients), and a comprehensive description of the viral and bacterial communities (via direct viral and microbial counts, enumeration of autofluorescent microbes, and construction of viral and microbial metagenomes). We use a combination of methods, which represent a dispersed field of scientific disciplines comprising already established protocols and some of the most recent techniques developed. Especially metagenomic sequencing techniques used for viral and bacterial community characterization, have been established only in recent years, and are thus still subjected to constant improvement. This has led to a variety of sampling and sample processing procedures currently in use. The set of methods presented here provides an up to date approach to collect and process environmental samples. Parameters addressed with these protocols yield the minimum on information essential to characterize and understand the underlying mechanisms of viral and microbial community dynamics. It gives easy to follow guidelines to conduct comprehensive surveys and discusses critical steps and potential caveats pertinent to each technique.

Here, we present a comprehensive protocol to assess the organic and inorganic nutrient availability and the abundance and structure of microbial and viral communities in remote marine environments.

揭开看不见的玩家在海洋 - 一个领域指南水化学和海洋微生物

Here we introduce a series of thoroughly tested and well standardized research protocols adapted for use in remote marine environments. The sampling ...

科研

环境科学

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and detritus, and excreting particulate and dissolved compounds, they serve as important agents for benthic-pelagic coupling. Accurately measuring the compounds removed and excreted by suspension feeders (such as sponges, ascidians, polychaetes, bivalves) is crucial for the study of their physiology, metabolism, and feeding ecology, and is fundamental to determine the ecological relevance of the nutrient fluxes mediated by these organisms. However, the assessment of the rate by which suspension feeders process particulate and dissolved compounds in nature is restricted by the limitations of the currently available methodologies. Our goal was to develop a simple, reliable, and non-intrusive method that would allow clean and controlled water sampling from a specific point, such as the excurrent aperture of benthic suspension feeders, in situ. Our method allows simultaneous sampling of inhaled and exhaled water of the studied organism by using minute tubes installed on a custom-built manipulator device and carefully positioned inside the exhalant orifice of the sampled organism. Piercing a septum on the collecting vessel with a syringe needle attached to the distal end of each tube allows the external pressure to slowly force the sampled water into the vessel through the sampling tube. The slow and controlled sampling rate allows integrating the inherent patchiness in the water while ensuring contamination free sampling. We provide recommendations for the most suitable filtering devices, collection vessel, and storing procedures for the analyses of different particulate and dissolved compounds. The VacuSIP system offers a reliable method for the quantification of undisturbed suspension feeder metabolism in natural conditions that is cheap and easy to learn and apply to assess the physiology and functional role of filter feeders in different ecosystems.

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

We introduce the VacuSIP, a simple, non-intrusive, and reliable method for clean and accurate point sampling of water. The system was developed and evaluated for the simultaneous collection of the water inhaled and exhaled by benthic suspension feeders in situ, to cleanly measure removal and excretion of particulate and dissolved compounds.

VacuSIP，对改进的方法INEX<em&gt;原位</em&gt;颗粒物与测量溶解的化合物加工后主动悬挂给料机

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and ...

Protocol for Microplastics Sampling on the Sea Surface and Sample Analysis

Microplastic pollution in the marine environment is a scientific topic that has received increasing attention over the last decade. The majority of scientific publications address microplastic pollution of the sea surface. The protocol below describes the methodology for sampling, sample preparation, separation and chemical identification of microplastic particles. A manta net fixed on an &#187;A frame&#171; attached to the side of the vessel was used for sampling. Microplastic particles caught in the cod end of the net were separated from samples by visual identification and use of stereomicroscopes. Particles were analyzed for their size using an image analysis program and for their chemical structure using ATR-FTIR and micro FTIR spectroscopy. The described protocol is in line with recommendations for microplastics monitoring published by the Marine Strategy Framework Directive (MSFD) Technical Subgroup on Marine Litter. This written protocol with video guide will support the work of researchers that deal with microplastics monitoring all over the world.

The protocol below describes the methodology for: microplastics sampling on the sea surface, separation of microplastic and chemical identification of particles. This protocol is in line with the recommendations for microplastics monitoring published by the MSFD Technical Subgroup on Marine Litter.

协议塑料微粒采样的海面和样品分析

Microplastic pollution in the marine environment is a scientific topic that has received increasing attention over the last decade. The majority of ...

Sampling, Sorting, and Characterizing Microplastics in Aquatic Environments with High Suspended Sediment Loads and Large Floating Debris

The ubiquitous presence of plastic debris in the ocean is widely recognized by the public, scientific communities, and government agencies. However, only recently have microplastics in freshwater systems, such as rivers and lakes, been quantified. Microplastic sampling at the surface usually consists of deploying drift nets behind either a stationary or moving boat, which limits the sampling to environments with low levels of suspended sediments and floating or submerged debris. Previous studies that employed drift nets to collect microplastic debris typically used nets with &#8805;300 &#181;m mesh size, allowing plastic debris (particles and fibers) below this size to pass through the net and elude quantification. The protocol detailed here enables: 1) sample collection in environments with high suspended loads and floating or submerged debris and 2) the capture and quantification of microplastic particles and fibers &lt;300 &#181;m. Water samples were collected using a peristaltic pump in low-density polyethylene (PE) containers to be stored before filtering and analysis in the lab. Filtration was done with a custom-made microplastic filtration device containing detachable union joints that housed nylon mesh sieves and mixed cellulose ester membrane filters. Mesh sieves and membrane filters were examined with a stereomicroscope to quantify and separate microplastic particulates and fibers. These materials were then examined using a micro-attenuated total reflectance Fourier transform infrared spectrometer (micro ATR-FTIR) to determine microplastic polymer type. Recovery was measured by spiking samples using blue PE particulates and green nylon fibers; percent recovery was determined to be 100% for particulates and 92% for fibers. This protocol will guide similar studies on microplastics in high velocity rivers with high concentrations of sediment. With simple modifications to the peristaltic pump and filtration device, users can collect and analyze various sample volumes and particulate sizes.

Most microplastic research to date has occurred in marine systems where suspended solid levels are relatively low. Focus is now shifting to freshwater systems, which may feature high sediment loads and floating debris. This protocol addresses collecting and analyzing microplastic samples from aquatic environments that contain high suspended solid loads.

高悬浮泥沙荷载和大型漂浮碎屑水生环境中 Microplastics 的取样、分类和表征

The ubiquitous presence of plastic debris in the ocean is widely recognized by the public, scientific communities, and government agencies. However, only ...

Design and Use of an Apparatus for Quantifying Bivalve Suspension Feeding at Sea

As shellfish aquaculture moves from coastal embayments and estuaries to offshore locations, the need to quantify ecosystem interactions of farmed bivalves (i.e., mussels, oysters, and clams) presents new challenges. Quantitative data on the feeding behavior of suspension-feeding mollusks is necessary to determine important ecosystem interactions of offshore shellfish farms, including their carrying capacity, the competition with the zooplankton community, the availability of trophic resources at different depths, and the deposition to the benthos. The biodeposition method is used to quantify feeding variables in suspension-feeding bivalves in a natural setting and represents a more realistic proxy than laboratory experiments. This method, however, relies upon a stable platform to satisfy the requirements that water flow rates supplied to the shellfish remain constant and the bivalves are undisturbed. A flow-through device and process for using the biodeposition method to quantify the feeding of bivalve mollusks were modified from a land-based format for shipboard use by building a two-dimensional gimbal table around the device. Planimeter data reveal a minimal pitch and yaw of the chambers containing the test shellfish despite boat motion, the flow rates within the chambers remain constant, and operators are able to collect the biodeposits (feces and pseudofeces) with sufficient consistency to obtain accurate measurements of the bivalve clearance, filtration, selection, ingestion, rejection, and absorption at offshore shellfish aquaculture sites.

A flow-through device for using the biodeposition method to quantify filtration and feeding behavior of bivalve mollusks was modified for shipboard use. A two-dimensional gimbal table built around the device isolates the apparatus from boat motion, thereby allowing the accurate quantification of bivalve filtration variables at offshore shellfish aquaculture sites.

海上双壳贝类悬浮饲料定量装置的设计与应用

As shellfish aquaculture moves from coastal embayments and estuaries to offshore locations, the need to quantify ecosystem interactions of farmed bivalves ...

Large Volume (20L+) Filtration of Coastal Seawater Samples

The workflow begins with the collection of coastal marine waters for downstream microbial community, nutrient and trace gas analyses. For this method, samples were collected from the deck of the HMS John Strickland operating in Saanich Inlet. This video documents large volume (&ge;20 L) filtration of microbial biomass, ranging between 0.22&mu;m and 2.7&mu;m in diameter, from the water column. Two 20L samples can be filtered simultaneously using a single pump unit equipped with four rotating heads. Filtration is done in the field on extended trips, or immediately upon return for day trips. It is important to record the amount of water passing through each sterivex filter unit. To prevent biofilm formation between sampling trips, all filtration equipment must be rinsed with dilute HCl and deionized water and autoclaved immediately after use. This procedure will take approximately 5 hours plus an additional hour for clean up.

Large Volume 20L+ Filtration of Coastal Seawater Samples

This video documents large volume (&ge;20 L) filtration of microbial biomass, ranging between 0.22&mu;m and 2.7&mu;m in diameter, from the water column.

大容量（20L）过滤沿海海水样品

The workflow begins with the collection of coastal marine waters for downstream microbial community, nutrient and trace gas analyses. For this method, ...

生物学

Small Volume (1-3L) Filtration of Coastal Seawater Samples

The workflow begins with the collection of coastal marine waters for downstream microbial community, nutrient and trace gas analyses. For today s demonstration samples were collected from the deck of the HMS John Strickland operating in Saanich Inlet. This video documents small volume (~1 L) filtration of microbial biomass from the water column. The protocol is an extension of the large volume sampling protocol described earlier, with one major difference: here, there is no pre-filtration step, so all size classes of biomass are collected down to the 0.22 &mu;m filter cut-off. Samples collected this way are ideal for nucleic acid analysis. The set-up, filtration, and clean-up steps each take about 20-30 minutes. If using two peristaltic pumps simultaneously, up to 8 samples may be filtered at the same time. To prevent biofilm formation between sampling trips, all filtration equipment must be rinsed with dilute HCl and deionized water and autoclaved immediately after use.

Small Volume 1-3L Filtration of Coastal Seawater Samples

This video documents small volume (~1 L) filtration of microbial biomass from the water column.

沿海海水样品的过滤体积小（1 - 3L）

The workflow begins with the collection of coastal marine waters for downstream microbial community, nutrient and trace gas analyses. For today s ...

A Microfluidic Platform for Precision Small-volume Sample Processing and Its Use to Size Separate Biological Particles with an Acoustic Microdevice

A major advantage of microfluidic devices is the ability to manipulate small sample volumes, thus reducing reagent waste and preserving precious sample. However, to achieve robust sample manipulation it is necessary to address device integration with the macroscale environment. To realize repeatable, sensitive particle separation with microfluidic devices, this protocol presents a complete automated and integrated microfluidic platform that enables precise processing of 0.15&#8211;1.5 ml samples using microfluidic devices. Important aspects of this system include modular device layout and robust fixtures resulting in reliable and flexible world to chip connections, and fully-automated fluid handling which accomplishes closed-loop sample collection, system cleaning and priming steps to ensure repeatable operation. Different microfluidic devices can be used interchangeably with this architecture. Here we incorporate an acoustofluidic device, detail its characterization, performance optimization, and demonstrate its use for size-separation of biological samples. By using real-time feedback during separation experiments, sample collection is optimized to conserve and concentrate sample. Although requiring the integration of multiple pieces of equipment, advantages of this architecture include the ability to process unknown samples with no additional system optimization, ease of device replacement, and precise, robust sample processing.

This protocol describes a system architecture for performing automated small volume (0.15&#8211;1.5 ml) particle separations using a microfluidic device, and discusses methods to optimize acoustofluidic device performance and operation.

微流体平台精密小批量来样加工及它的使用尺寸分离生物颗粒的声微型

A major advantage of microfluidic devices is the ability to manipulate small sample volumes, thus reducing reagent waste and preserving precious sample. ...

生物工程

Separation and Identification of Conventional Microplastics from Farmland Soils

Microplastics (MPs) pollution in the terrestrial environment has received increasing attention over the last decade, with increasing studies describing the numbers and types of MPs in different soil systems and their impacts on soil and crop health. However, different MPs extraction and analytical methods are used, limiting opportunities to compare results and generate reliable evidence for industry advice and policymakers. Here, we present a protocol that describes the methodology for sampling, separation, and chemical identification of conventional MPs&#160;from soil. The method is low-cost, and the materials are readily available. This enhances operational ease and may help with widespread adoption. The protocol provides detailed information on sample collection from the top 0-30 cm of soil using plastic-free utensils; simulation of different soil types through the use of various solid media (such as bentonite clay, silicon dioxide, and non-contaminated soil), with the addition of the same mass&#160;of polyethylene(PE)-MPs for subsequent quantification; density separation of plastic particles utilizing saturated sodium chloride (NaCl) solution and digestion of organic impurities in the supernatant using 4 M sodium hydroxide (NaOH) solution; quantification of particles using fluorescent microscopy after Nile Red staining; and polymer identification using micro&#160;Fourier-Transform Infrared Spectroscopy (&#956;-FTIR) or Laser-Direct Infrared (LDIR) spectroscopy. The MPs recovery rate ranged from 83% - 90% for the abovementioned media. This protocol presents an efficient method for soil MPs analysis that is optimized for feasibility, applicability, and cost-effectiveness. Moreover, the video accompanied can guide the process of analyzing the soil MPs step-by-step virtually. This study is dedicated to standardizing the methods for soil MPs analysis, enhancing the connectivity and comparability of measurements, and establishing a foundation for more standardized and scientific research.

Presented here is a method for extracting microplastics from soil and identifying their polymer types. The method has been optimized for execution, applicability, and cost-effectiveness. It lays a scientific foundation for standardizing the analytical method to identify microplastics in soils.

农田土壤中常规微塑料的分离和鉴定

Microplastics (MPs) pollution in the terrestrial environment has received increasing attention over the last decade, with increasing studies describing ...

用于从人尿液中连续分离细胞外囊泡的微流控装置

Single Step Isolation of Extracellular Vesicles from Large-Volume Samples with a Bifurcated A4F Microfluidic Device

Extracellular vesicles (EVs) hold immense potential for various biomedical applications, including diagnostics, drug delivery, and regenerative medicine. Nevertheless, the current methodologies for isolating EVs present significant challenges, such as complexity, time consumption, and the need for bulky equipment, which hinders their clinical translation. To address these limitations, we aimed to develop an innovative microfluidic system based on cyclic olefin copolymer-off-stoichiometry thiol-ene (COC-OSTE) for the efficient isolation of EVs from large-volume samples in a continuous manner. By utilizing size and buoyancy-based separation, the technology used in this study achieved a significantly narrower size distribution compared to existing approaches from urine and cell media samples, enabling the targeting of specific EV size fractions in future applications. Our innovative COC-OSTE microfluidic device design, utilizing bifurcated asymmetric flow field-flow fractionation technology, offers a straightforward and continuous EV isolation approach for large-volume samples. Furthermore, the potential for mass manufacturing of this microfluidic device offers scalability and consistency, making it feasible to integrate EV isolation into routine clinical diagnostics and industrial processes, where high consistency and throughput are essential requirements.

作者聚焦：用于生物反应器集成的不对称场流分离

Extracellular vesicles hold immense promise for biomedical applications, but current isolation methods are time-consuming and impractical for clinical use. In this study, we present a microfluidic device that enables the direct isolation of extracellular vesicles from large volumes of biofluids in a continuous manner with minimal steps.

使用分叉 A4F 微流控装置从大体积样品中单步分离细胞外囊泡

Extracellular vesicles (EVs) hold immense potential for various biomedical applications, including diagnostics, drug delivery, and regenerative medicine. ...