这项研究得到了基础科学研究项目 (项目编号: 2016R1A2B4013467) 的支持, 通过韩国国家研究基金会 (NRF), 由科学部、信息和通信技术 & 未来规划2016提供资金, 并得到韩国基础科学的支持。研究所研究计划 (项目编号: C36707)。

1. DMMTA 的合成V
<ol><li>
化学制剂和摩尔比混合 DMAV, Na2S, 和 H2, 所以4 注意: DMAV: Na2S: H2所以4 = 1:1. 6:1. 6<ol>
<li>将 5.24 g 的 DMAV溶解在40毫升去离子和 N2中 (在50毫升离心管中清洗至少30分钟) 水。</li>
		<li>通过溶解14.41 克 na2S·9H2O 在50毫升去离子和 N2-被清洗的水在250毫升瓶中, 准备 na2S 试剂。</li>
		<li>准备 H2, 以便4试剂通过在40毫升离心管中添加3.3 毫升的浓硫酸 (96%) 至2毫升去离子和 N50清除水。 注意:DMA 的最终摩尔比率V: Na2S: H2所以4 = 1:1. 6:1. 6 13,4,8,15。</li>
		<li>将已准备好的40毫升 DMAV解决方案 (步骤 1.1.1) 添加到250毫升烧瓶 (步骤 1.1.2) 中包含的 Na2S 解决方案的50毫升。冲洗包含 DMAV的10毫升清洗水的管, 并将其添加到250毫升烧瓶中。</li>
		<li>用装有玻璃管的三孔橡胶塞子关闭烧瓶。分别使用用于 N2气体流入、流出和 H2的玻璃管, 因此4解决方案入口。关闭烧瓶后立即, 允许 N2气体流入烧瓶中。 注: 应保持气体压力, 以在反应溶液表面流动而不飞溅。</li>
		<li>将耐酸油管连接到 H2的玻璃管, 使4溶液入口与50毫升注射器一起添加准备好的40毫升的 h2, 因此4解决方案 (步骤 1.1.3)。添加40毫升的 H2, 所以4解决方案, 慢慢地和逐步地。 警告:加入硫酸后, 会产生白烟;使用通风良好的油烟罩。</li>
		<li>定期添加硫酸时, 监测反应混合物在烧瓶中的颜色变化。保持间隔为 4-5 毫升的 H2, 因此4;混合物应该是一个白色的多云溶液。 注: 由于浓硫酸的快速添加, 瞬时黄沉淀可能出现。</li>
		<li>确保反应解决方案自1.1.4 开始以来一直保持1小时。</li>
	</ol>
</li>
	<li>
用液-液萃取法提取 DMMTAV
	<ol>
<li>1小时后, 将反应溶液倒入含有大约200毫升乙醚的部位漏斗中。</li>
		<li>摇动漏斗 5-10 分钟, 释放气体几次通过切换旋塞阀。 注意: 合成的 DMMTAV将被转移到二乙基醚 (0.713 g·mL-1) 的上层。 警告:乙醚气体可能有害;使用通风良好的油烟罩。</li>
		<li>在烧杯中收集反应溶液, 并分别收集含有 DMMTAV的二乙基醚。将反应溶液放回同一部位漏斗中, 加入约200毫升的新鲜二乙基醚 reshaking。重复步骤 1.2.2-1.2.3 三次。</li>
		<li>再将所收集的二乙基醚从步骤1.2.3 倒入同一部位漏斗中, 并添加约100毫升 N2-清除去离子水。摇动 5-10 分钟, 并丢弃 N2-清除去离子水和几毫升二乙基醚为纯净目的。在玻璃培养皿中收集剩余的二乙基醚 (最小内径为160毫米, 最小高度为50毫米)。</li>
		<li>将玻璃培养皿转移到 N2大气手套盒中, 以防止物种转化。 警告:确保溶剂不被拉入真空泵通过出口的通行证箱。</li>
		<li>干燥直到 dimethylmonothioarsinate 的白色沉淀 (结晶 DMMTAV) 在玻璃培养皿上形成。 注意: 协议可以在这里暂停。</li>
	</ol>
</li>
	<li>
对合成 DMMTAV和存储的验证
	<ol>
<li>采取结晶 DMMTAV的白色沉淀, 并测量并记录其总重量。 警告:使用通风良好的油烟罩或手套箱, 防止吸入硫化氢气体。</li>
		<li>将结晶 DMMTAV分解为50毫升的 N2-清除去离子水, 并通过 0.2-µm 注射器过滤器过滤黄色沉淀。</li>
		<li>假定已使用的 DMAv的总计转换为 DMMTAv,即≈9,649 mg As·L-1。稀释 DMMTAV库存解决方案≈1毫克·L-1和≈40µg·L-1分别使用电喷雾电离质量 Spectromtery (ESI) 和 HPLC-电感耦合-ms 进行验证分析。</li>
		<li>使用ESI (MS11)16和在m/z 155 中的片段在正离子模式下或m/z 153 中的负离子模式 (表 1) 中, 分析 DMMTAV的m/z 。 注意: 请参阅m/z的引用值 (表 1)。</li>
		<li>用高效液相色谱-ICP-MS11,16,17 , 用适当的淋洗条件分析股票溶液中 DMMTAV的色谱, 并确认主要峰值在文学. 注意: 应使用步骤1.3.5 中的分析结果计算合成 DMMTAV的纯度。</li>
		<li>用 ICP-质谱分析酸消化后的总砷浓度11 , 并用稀释因子和纯度计算合成 DMMTAv库存溶液中的真实 DMMTAv浓度, 如下面的公式所示: 分析合计为浓度 (µg·L-1) ·稀释因素·纯度 (%) = True DMMTAv集中在 DMMTAv库存解决方案 (µg·L-1)</li>
		<li>存储 DMMTAV库存解决方案在4°c 在黑暗中进一步定量形态分析18。</li>
	</ol>
</li>
</ol>2. DMDTA 的合成V
<ol><li>
化学制剂和摩尔比混合 DMAV , Na2S, 和 H2, 所以4 注意: DMAV: Na2S: H2所以4 = 1:7. 5:7. 5<ol>
<li>在50毫升离心管中, 将1.38 克的 DMAV溶解在40毫升去离子水中。</li>
		<li>通过在50毫升去离子水中溶解18.01 克 na2S·9H2O, 将钠2的试剂制备为一瓶。</li>
		<li>准备 H2, 使4试剂添加4毫升浓硫酸 (96%) 到40毫升的去离子水中, 其中含有50毫升离心管。 注意:DMA 的最终摩尔比率V: Na2S: H2所以4 = 1:7. 5:7. 513,4,8,15。</li>
		<li>将已准备好的40毫升 DMAV解决方案 (步骤 2.1.1) 添加到250毫升烧瓶 (步骤 2.1.2) 中包含的 Na2S 解决方案的50毫升。用10毫升去离子水冲洗含有 DMAV的管, 并将其添加到250毫升烧瓶中。</li>
		<li>将准备好的40毫升 H2, 使4解决方案 (步骤 2.1.3), 慢慢地和逐步地, 进入烧瓶。</li>
		<li>定期添加硫酸时, 监测反应混合物在烧瓶中的颜色变化。保持间隔为 4-5 毫升的 H2, 因此4;混合物应为白色/黄色多云溶液。 注: 由于浓硫酸的快速添加, 瞬时黄沉淀可能会出现。 警告:加入硫酸后, 会产生白烟;使用通风良好的油烟罩。</li>
		<li>在瓶中保持反应液过夜不覆盖。 注意: 协议可以在这里暂停。</li>
	</ol>
</li>
	<li>
使用固相萃取 (SPE) 方法提取的 DMDTAV
	<ol>
<li>在隔夜反应之后, 用 C18 注射器型硅基 SPE 过滤反应溶液, 以便在树脂上捕获合成的 DMDTAV 。 警告:使用通风良好的油烟罩。</li>
		<li>用10毫米醋酸铵 (pH 6.3) 将0.77 克醋酸铵溶解在去离子水的1升中。通过 C18 注射器 (步骤 2.2.1) 洗脱足够的10毫米醋酸铵, 提取吸附 DMDTA V.在玻璃培养皿中收集过滤过的醋酸铵 (最小内径为160毫米, 最小高度为50毫米)。</li>
		<li>将玻璃培养皿转移到 N2大气手套盒中, 以防止物种转化。 警告:确保溶剂不被拉入真空泵通过出口的通行证箱。</li>
		<li>干燥直到 dimethyldithioarsinate 的白色沉淀形成 (结晶 DMDTAV) 在玻璃培养皿上。 注意: 协议可以在这里暂停。</li>
	</ol>
</li>
	<li>
对合成 DMDTAV和存储的验证
	<ol>
<li>取结晶 DMDTAV的白色沉淀, 并测量其总重量, 记录测量结果。 警告:使用通风良好的油烟罩或手套箱, 防止吸入硫化氢气体。</li>
		<li>在50毫升的 N2中溶解结晶 DMDTAV -在50毫升离心管中清除去离子水, 并通过 0.2-µm 注射器过滤器过滤任何沉淀。</li>
		<li>假定已使用的 DMAV的总计转换为 DMDTAv,即≈2,539 mg As·L-1。稀释 DMDTAV库存解决方案≈1毫克·L-1和≈40µg·L-1分别使用 ESI-ms 和高效液相色谱-ms 进行验证分析。</li>
		<li>使用ESI (MS11)16和在m/z 171 中的片段在正离子模式下或m/z 169 中的负离子模式 (表 1) 中, 分析 DMDTAV的m/z 。 注意: 请参阅m/z的引用值 (表 1)。</li>
		<li>用高效液相色谱-ICP-MS11,16,17 ,用适当的淋洗条件分析 DMDTA 中的V的色谱, 并确认在保留时间内发现的峰值文学。 注意: 应使用步骤2.3.5 中的分析结果计算合成 DMDTAV的纯度。</li>
		<li>用 ICP-质谱分析酸消化后的总砷浓度11 , 并用稀释因子和纯度计算合成 DMDTAv库存溶液中的真 DMDTAv浓度如下方程式: 分析合计为浓度 (µg·L-1) ·稀释因素·纯度 (%) = True DMDTAv在库存解决方案中 DMDTAv的浓度 (µg·L-1)</li>
		<li>存储 DMDTAV库存解决方案在4°c 在黑暗中进一步定量形态分析18。</li>
	</ol>
</li>
</ol>

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Toxicol. 26, 952-962 (2013).</li><li>Alava, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=HPLC-ICP-MS+method+development+to+monitor+arsenic+speciation+changes+by+human+gut+microbiota.">HPLC-ICP-MS method development to monitor arsenic speciation changes by human gut microbiota.</a> Biomed. Chromatogr. 26, 524-533 (2012).</li><li>Kurosawa, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+metabolic+activation+associated+with+glutathione+in+dimethylmonoarsinic+acid+(DMMTAV)-induced+toxicity+obtained+from+in+vitro+reaction+of+DMMTAV+with+glutathione.">A novel metabolic activation associated with glutathione in dimethylmonoarsinic acid (DMMTAV)-induced toxicity obtained from in vitro reaction of DMMTAV with glutathione.</a> J. trace Elem. Med. Biol. 33, 87-94 (2016).</li></ol>

作者没有什么可透露的。

已开发的协议澄清了以前研究的关键步骤1,3,4,8,15省略或缩写, 这可能导致困难或失败期间DMMTAv和 DMDTAv合成。由于 DMMTAV是氧化敏感的1,5, 使用 N2清除的去离子水 (步骤 1.1.1-1.1.3) 来制备合成试剂, 以防...

由于 dimethylarsinic 酸 (DMAV) 已被证明表现出急性毒性和遗传毒性由于正在接受甲基化和 thiolation 在摄取1,2, 砷 thiolation 的代谢途径有深入研究了体外和体内3,4以及环境介质 (例如,垃圾渗滤液)5,6。以前的研究在活细胞中发现了 DMAV的减少和 thiolated 类似物, 例如、 dimethylarsinous 酸 (DMAIII)、dimethylmonothioarsinic 酸 (DMMTAV) 和 dimethyldithioarsinic 酸 (DMDTAV)7,8,9, 与 dimethylated thioarsenicals 如 DMMTAV显示更大的毒性比其他已知的无机或有机砷10。高毒性 thioarsenicals 的丰度具有严重的环境影响, 因为它们在高度 sulfidic 条件下可能对人类和环境构成风险11。然而, DMMTAv和 DMDTAv (横贯) 形成的机制及其在环境媒体中的命运仍然需要进一步研究。因此, 需要对 thioarsenicals 进行定量分析, 以提高对 DMMTAv和 DMDTAv的环境影响的理解。
虽然标准化学品是定量分析的关键要求, 但由于物种转化为其他物种的风险很高, DMMTAv和 DMDTAv的标准很难通过复制以前的研究获得。原始社会合成过程12。此外, 所提到的方法有局限性, 可能会导致在合成标准化学品和进行定量分析的实际困难。DMMTAv和 DMDTAv通常是通过 dmav 2的解决方案混合 dmav、Na2和 H2, 所以4在某摩尔比率1或冒泡 H1314的气体中进行的。冒泡方法使用 H2S 气体的直接供应, 以硫磺代替氧气, 这是剧毒和难以控制的经验不足的用户。相反, 上述混合方法1, 广泛用于定性分析 DMMTAv和 DMDTAV在环境研究5,6,12, 功能 thiolation使用 H2生成的 DMAV由混合 Na2s 和 H2, 因此4和生产 DMMTAv和 DMDTAv, 允许更容易的化学计量控制生产目标化学品, 与直接使用 H2的气体。
参考混合方法过程1,3,4,8,15在本研究中提到的一些关键实验步骤的局限性, 这可能导致实验失败。例如, 具体溶剂的详细情况 (即,去离子水) 的制备和合成砷的提取和结晶是过于缩写或没有充分详细说明。有关程序性步骤的这种分散和有限的信息可能导致 thioarsenicals 的不一致形成和不可靠的量化分析。因此, 本文所开发的修改后的协议描述了 DMMTAv和 DMDTAv库存解决方案的合成, 并进行了定量的物种分离分析。

<table width="712">
	<tbody>
		<tr height="21">
			<td height="21" style="width:179px;height:21px;">Cacodylic acid</td>
			<td style="width:179px;">Sigma-Aldrich</td>
			<td style="width:179px;">20835-10G-F</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:179px;height:42px;">Sodium sulfide nonahydrate</td>
			<td style="width:179px;">Sigma-Aldrich</td>
			<td style="width:179px;">S2006-500G</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:179px;height:21px;">Sulfuric acid 96%</td>
			<td style="width:179px;">J.T.Baker</td>
			<td style="width:179px;">0000011478</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:179px;height:21px;">Ammonium acetate</td>
			<td style="width:179px;">Sigma-Aldrich</td>
			<td style="width:179px;">A7262-500G</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:179px;height:42px;">Formic acid 98%</td>
			<td style="width:179px;">Wako Pure Chemical Industries, Ltd.</td>
			<td style="width:179px;">066-00461</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:179px;height:21px;">Diethyl ether (Extra Pure)</td>
			<td style="width:179px;">Junsei Chemical</td>
			<td style="width:179px;">33475-0380</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:179px;height:42px;">Adapter cap for 60 mL Bond Elut catridges</td>
			<td style="width:179px;">Agilent Technologies</td>
			<td style="width:179px;">12131004</td>
			<td>Syringe type of SPE</td>
		</tr>
		<tr height="21">
			<td height="21" style="width:179px;height:21px;">Bond Elut C18 cartridge</td>
			<td style="width:179px;">Agilent Technologies</td>
			<td style="width:179px;">14256031</td>
			<td>Syringe type of SPE</td>
		</tr>
		<tr height="21">
			<td height="21" style="width:179px;height:21px;">HyPURITY C-18</td>
			<td style="width:179px;">Thermo Scientific</td>
			<td style="width:179px;">22105-254630</td>
			<td>5 um, 125 x 4.6 mm</td>
		</tr>
		<tr height="42">
			<td height="42" style="width:179px;height:42px;">Glovebox</td>
			<td style="width:179px;">Chungae-chun, Rep. of Korea</td>
			<td style="width:179px;"></td>
			<td>Customized&#160;</td>
		</tr>
		<tr height="42">
			<td height="42" style="width:179px;height:42px;">Agilent 1260 Infinity Bio-inert LC</td>
			<td style="width:179px;">Agilent Technologies</td>
			<td style="width:179px;">DEAB600252, DEACH00245</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:179px;height:42px;">Agilent Technologies 7700 Series ICP-MS</td>
			<td style="width:179px;">Agilent Technologies</td>
			<td style="width:179px;">JP12031510</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="width:179px;height:63px;">Finnigan LCQ Deca XP MAX Mass Spectrometer System</td>
			<td style="width:179px;">Thermo Electron Corporation</td>
			<td style="width:179px;">LDM10627</td>
			<td></td>
		</tr>
	</tbody>
</table>

preparation of dmmtav and dmdtav using dmav for environmental applications: synthesis, purification, and confirmation

Dimethylated thioarsenicals, 如 dimethylmonothioarsinic 酸 (DMMTAV) 和 dimethyldithioarsinic 酸 (DMDTAv), 是由 dimethylarsinic 酸 (DMAV) thiolation 的新陈代谢途径产生的, 最近在环境和人体器官中发现的。DMMTAv和 DMDTAv可以量化, 以确定 dimethylated thioarsenicals 的生态效应及其在环境介质中的稳定性。这些化合物的合成方法是原始社会的, 使得复制以前的研究具有挑战性。此外, 缺乏关于储存技术的信息, 包括没有物种转化的化合物的储存。此外, 由于只有有限的合成方法信息, 在合成标准化学品和进行定量分析方面可能存在实验困难。本文提出的协议为 dimethylated thioarsenicals、DMMTAv和 DMDTAv提供了一个实际改进的合成方法, 并将有助于利用高性能液体进行物种分离分析的量化。用电感耦合等离子体质谱 (HPLC-ICP) 相结合的色谱法。通过对化学试剂的制备、过滤方法和贮存的研究, 对该过程的实验步骤进行了改进。

由于 DMAIII合成方法19错误地编写了 DMMTAV , 因此对合成的 DMMTAv和 DMDTAv的验证是合成和提取和确定理想标准的关键步骤。化学材料。合成化学物质可以通过 DMMTAV (兆瓦 154 g·mol-1) 和 DMDTAV (兆瓦 170 g·mol-1) 质量-电荷比 (m/z) 的峰值来验证, 使用的是电喷雾电离质量的正负离子模式。通过?...

Watch this Scientific Journal Video about Preparation of DMMTAV and DMDTAV Using DMAV for Environmental Applications: Synthesis, Purification, and Confirmation at JoVE.com

Preparation of DMMTAV and DMDTAV Using DMAV for Environmental Applications: Synthesis, Purification, and Confirmation

使用 DMAv为环境应用 DMMTAv和 DMDTAv的准备: 合成、纯化和确认

本文介绍了 dimethylmonothioarsinic 酸 (DMMTAv) 和 dimethyldithioarsinic 酸 (DMDTAv) 合成、诱导 dimethylarsinic 酸 (dmav) thiolation 通过混合 DMAv 的改进实验协议。, Na2S, 和 H2, 所以4。修改后的协议提供了实验指导, 从而克服了在定量分析过程中可能导致实验失败的综合步骤的局限性。

Dimethylated thioarsenicals such as dimethylmonothioarsinic acid (DMMTAV) and dimethyldithioarsinic acid (DMDTAV), which are produced by the metabolic ...

preparation-dmmtav-dmdtav-using-dmav-for-environmental-applications

Universidad San Sebastian

Research

JoVE Journal

Environment

Preparation of DMMTAV and DMDTAV Using DMAV for Environmental Applications: Synthesis, Purification, and Confirmation

5.4K 次观看.  Korea Basic Science Institute, Seoul Center. 本文介绍了 dimethylmonothioarsinic 酸 (DMMTAv) 和 dimethyldithioarsinic 酸 (DMDTAv) 合成、诱导 dimethylarsinic 酸 (dmav) thiolation 通过混合 DMAv 的改进实验协议。, Na2S, 和 H2, 所以4。修改后的协议提供了实验指导, 从而克服了在定量分析过程中可能导致实验失败的综合步骤的局限性。

视频: Preparation of DMMTAV and DMDTAV Using DMAV for Environmental Applications: Synthesis, Purification, and Confirmation

Waste Water Derived Electroactive Microbial Biofilms: Growth, Maintenance, and Basic Characterization

The growth of anodic electroactive microbial biofilms from waste water inocula in a fed-batch reactor is demonstrated using a three-electrode setup controlled by a potentiostat. Thereby the use of potentiostats allows an exact adjustment of the electrode potential and ensures reproducible microbial culturing conditions. During growth the current production is monitored using chronoamperometry (CA). Based on these data the maximum current density (jmax) and the coulombic efficiency (CE) are discussed as measures for characterization of the bioelectrocatalytic performance. Cyclic voltammetry (CV), a nondestructive, i.e. noninvasive, method, is used to study the extracellular electron transfer (EET) of electroactive bacteria. CV measurements are performed on anodic biofilm electrodes in the presence of the microbial substrate, i.e. turnover conditions, and in the absence of the substrate, i.e. nonturnover conditions, using different scan rates. Subsequently, data analysis is exemplified and fundamental thermodynamic parameters of the microbial EET are derived and explained: peak potential (Ep), peak current density (jp), formal potential (Ef) and peak separation (&#916;Ep). Additionally the limits of the method and the state-of the art data analysis are addressed. Thereby this video-article shall provide a guide for the basic experimental steps and the fundamental data analysis.

Chronoamperometric growth of anodic electroactive microbial biofilms in a fed-batch reactor using a three-electrode setup, controlled by a potentiostat, is demonstrated. The extracellular electron transfer is characterized using cyclic voltammetry in the presence of the electron donor and in the absence of the electron donor. Fundamental data analysis is demonstrated.

The growth of anodic electroactive microbial biofilms from waste water inocula in a fed-batch reactor is demonstrated using a three-electrode setup ...

科研

环境科学

A Whole Cell Bioreporter Approach to Assess Transport and Bioavailability of Organic Contaminants in Water Unsaturated Systems

Bioavailability of contaminants is a prerequisite for their effective biodegradation in soil. The average bulk concentration of a contaminant, however, is not an appropriate measure for its availability; bioavailability rather depends on the dynamic interplay of potential mass transfer (flux) of a compound to a microbial cell and the capacity of the latter to degrade the compound. In water-unsaturated parts of the soil, mycelia have been shown to overcome bioavailability limitations by actively transporting and mobilizing organic compounds over the range of centimeters. Whereas the extent of mycelia-based transport can be quantified easily by chemical means, verification of the contaminant-bioavailability to bacterial cells requires a biological method. Addressing this constraint, we chose the PAH fluorene (FLU) as a model compound and developed a water unsaturated model microcosm linking a spatially separated FLU point source and the FLU degrading bioreporter bacterium Burkholderia sartisoli RP037-mChe by a mycelial network of Pythium ultimum. Since the bioreporter expresses eGFP in response of the PAH flux to the cell, bacterial FLU exposure and degradation could be monitored directly in the microcosms via confocal laser scanning microscopy (CLSM). CLSM and image analyses revealed a significant increase of the eGFP expression in the presence of P. ultimum compared to controls without mycelia or FLU thus indicating FLU bioavailability to bacteria after mycelia-mediated transport. CLSM results were supported by chemical analyses in identical microcosms. The developed microcosm proved suitable to investigate contaminant bioavailability and to concomitantly visualize the involved bacteria-mycelial interactions.

A whole cell bioreporter assay with Burkholderia sartisoli RP037-mChe was developed to detect fractions of an organic contaminant (i.e., fluorene) available for bacterial degradation after active transport by mycelia bridging air-filled pores in a water unsaturated model system.

全细胞Bioreporter方法​​评估交通有机污染物的生物利用度和水饱和系统

Bioavailability of contaminants is a prerequisite for their effective biodegradation in soil. The average bulk concentration of a contaminant, however, is ...

Preparation and Testing of Impedance-based Fluidic Biochips with RTgill-W1 Cells for Rapid Evaluation of Drinking Water Samples for Toxicity

This manuscript describes how to prepare fluidic biochips with Rainbow trout gill epithelial (RTgill-W1) cells for use in a field portable water toxicity sensor. A monolayer of RTgill-W1 cells forms on the sensing electrodes enclosed within the biochips. The biochips are then used for testing in a field portable electric cell-substrate impedance sensing (ECIS) device designed for rapid toxicity testing of drinking water. The manuscript further describes how to run a toxicity test using the prepared biochips. A control water sample and the test water sample are mixed with pre-measured powdered media and injected into separate channels of the biochip. Impedance readings from the sensing electrodes in each of the biochip channels are measured and compared by an automated statistical software program. The screen on the ECIS instrument will indicate either "Contamination Detected" or "No Contamination Detected" within an hour of sample injection. Advantages are ease of use and rapid response to a broad spectrum of inorganic and organic chemicals at concentrations that are relevant to human health concerns, as well as the long-term stability of stored biochips in a ready state for testing. Limitations are the requirement for cold storage of the biochips and limited sensitivity to cholinesterase-inhibiting pesticides. Applications for this toxicity detector are for rapid field-portable testing of drinking water supplies by Army Preventative Medicine personnel or for use at municipal water treatment facilities.

This manuscript describes how to prepare fluidic biochips with Rainbow trout gill epithelial cells for use in a field portable electric cell-substrate impedance sensor. The protocol for running a rapid drinking water toxicity test with the sensor is also described.

准备和测试阻抗为基础与RTgill-W1细胞饮用水进行快速评估水样进行毒性射流生物芯片

This manuscript describes how to prepare fluidic biochips with Rainbow trout gill epithelial (RTgill-W1) cells for use in a field portable water toxicity ...

The Benthic Exchange of O2, N2 and Dissolved Nutrients Using Small Core Incubations

The measurement of sediment-water exchange of gases and solutes in aquatic sediments provides data valuable for understanding the role of sediments in nutrient and gas cycles. After cores with intact sediment-water interfaces are collected, they are submerged in incubation tanks and kept under aerobic conditions at in situ temperatures. To initiate a time course of overlying water chemistry, cores are sealed without bubbles using a top cap with a suspended stirrer. Time courses of 4-7 sample points are used to determine the rate of sediment water exchange. Artificial illumination simulates day-time conditions for shallow photosynthetic sediments, and in conjunction with dark incubations can provide net exchanges on a daily basis. The net measurement of N2 is made possible by sampling a time course of dissolved gas concentrations, with high precision mass spectrometric analysis of N2:Ar ratios providing a means to measure N2 concentrations. We have successfully applied this approach to lakes, reservoirs, estuaries, wetlands and storm water ponds, and with care, this approach provides valuable information on biogeochemical balances in aquatic ecosystems.

The Benthic Exchange of O2, N2 and Dissolved Nutrients Using Small Core Incubations

Here, we present small core incubations for the measurement of sediment-water gas and solute exchange. These will provide reliable measurements of sediment-water exchange that assess the role of sediment in influencing biological and biogeochemical processes in aquatic ecosystems.

Ø的底栖交易所<sub&gt; 2</sub&gt;，N<sub&gt; 2</sub&gt;和营养盐使用小的核心孵化

The measurement of sediment-water exchange of gases and solutes in aquatic sediments provides data valuable for understanding the role of sediments in ...

Use of a Filter Cartridge for Filtration of Water Samples and Extraction of Environmental DNA

Recent studies demonstrated the use of environmental DNA (eDNA) from fishes to be appropriate as a non-invasive monitoring tool. Most of these studies employed disk fiber filters to collect eDNA from water samples, although a number of microbial studies in aquatic environments have employed filter cartridges, because the cartridge has the advantage of accommodating large water volumes and of overall ease of use. Here we provide a protocol for filtration of water samples using the filter cartridge and extraction of eDNA from the filter without having to cut open the housing. The main portions of this protocol consists of 1) filtration of water samples (water volumes &#8804;4 L or &gt;4 L); (2) extraction of DNA on the filter using a roller shaker placed in a preheated incubator; and (3) purification of DNA using a commercial kit. With the use of this and previously-used protocols, we perform metabarcoding analysis of eDNA taken from a huge aquarium tank (7,500 m3) with known species composition, and show the number of detected species per library from the two protocols as the representative results. This protocol has been developed for metabarcoding eDNA from fishes, but is also applicable to eDNA from other organisms.

We describe a protocol for filtration of water samples with a filter cartridge and extraction of environmental DNA (eDNA) without having to cut open the housing to remove the filter. This protocol is developed for metabarcoding eDNA from fishes, but is also applicable to eDNA from other organisms.

滤芯水过滤样品和环境DNA的提取使用

Recent studies demonstrated the use of environmental DNA (eDNA) from fishes to be appropriate as a non-invasive monitoring tool. Most of these studies ...

Resurrection of Dormant Daphnia magna: Protocol and Applications

Long-term studies enable the identification of eco-evolutionary processes that occur over extended time periods. In addition, they provide key empirical data that may be used in predictive modelling to forecast evolutionary responses of natural ecosystems to future environmental changes. However, excluding a few exceptional cases, long-term studies are scarce because of logistic difficulties associated with accessing temporal samples. Temporal dynamics are frequently studied in the laboratory or in controlled mesocosm experiments with exceptional studies that reconstruct the evolution of natural populations in the wild.
Here, a standard operating procedure (SOP) is provided to revive or resurrect dormant Daphnia magna, a widespread zooplankton keystone species in aquatic ecosystems, to dramatically advance the state-of-the-art longitudinal data collection in natural systems. The field of Resurrection Ecology was defined in 1999 by Kerfoot and co-workers, even though the first attempts at hatching diapausing zooplankton eggs date back to the late 1980s. Since Kerfoot&#39;s seminal paper, the methodology of resurrecting zooplankton species has been increasingly frequently applied, though propagated among laboratories only via direct knowledge transfer. Here, an SOP is described that provides a step-by-step protocol on the practice of resurrecting dormant Daphnia magna eggs.
Two key studies are provided in which the fitness response of resurrected Daphnia magna populations to warming is measured, capitalizing on the ability to study historical and modern populations in the same settings. Finally, the application of next generation sequencing technologies to revived or still dormant stages is discussed. These technologies provide unprecedented power in dissecting the processes and mechanisms of evolution if applied to populations that have experienced changes in selection pressure over time.

Resurrection of Dormant Daphnia magna: Protocol and Applications

Long-term studies are essential to understanding the process of evolution and the mechanisms of adaptation. Generally, these studies require commitments beyond the life-time of researchers. Here, a powerful method is described that dramatically advances state-of-the-art data collection to generate longitudinal data in natural systems.

休眠蚤的复活: 协议和应用

Long-term studies enable the identification of eco-evolutionary processes that occur over extended time periods. In addition, they provide key empirical ...

Composition and Distribution Analysis of Bioaerosols Under Different Environmental Conditions

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, we described a protocol for multiple analyses of the biological compositions in environmental PM. Five experiments are presented: (1) PM number monitoring by using a laser particle counter; (2) PM collection by using a cyclonic aerosol sampler; (3) PM collection by using a high-volume air sampler with filters; (4) culturable microbes collection by the Andersen six-stage sampler; and (5) detection of biological composition of environmental PM by bacterial 16SrDNA and fungal ITS region sequencing. We selected hazy days and a livestock farm as two typical examples of the application in this protocol. In this study, these two sampling methods, cyclonic aerosol sampler and filter sampler, showed different sampling efficiency. The cyclonic aerosol sampler performed much better in terms of collecting bacteria, while these two methods showed the same efficiency in collecting fungi. Filter samplers can work under low temperature conditions while cyclonic aerosol samplers have a sampling limitation for temperature. A solid impacting sampler, such as an Andersen six-stage sampler, can be used to sample bioaerosols directly into the culture medium, which increases the survival rate of culturable microorganisms. However, this method mainly relies on culture while more than 99% of microbes cannot be cultured. DNA extracted from the culturable bacteria collected by the Andersen six-stage sampler and samples collected by cyclonic aerosol sampler and filter sampler were detected by bacterial 16S rDNA and fungal ITS region sequencing.All the methods above may have wide application in many fields of study, such as environmental monitoring and airborne pathogen detection. From these results, we can conclude that these methods can be used under different conditions and may help other researchers further explore the health impacts of environmental bioaerosols.

Understanding the biological composition of environmental particulate matter is important for the study of its significant impacts on human health and disease spread. Here, we used three types of bioaerosol sampling methods and a biological analysis of airborne microbes to better explore airborne microbial communities under different environmental conditions.

不同环境条件下生物气溶胶的组成及分布分析

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, ...

Identifying Per- and Polyfluorinated Chemical Species with a Combined Targeted and Non-Targeted-Screening High-Resolution Mass Spectrometry Workflow

Historical and emerging per- and polyfluoroalkyl substances (PFASs) have garnered significant interest from the public and government agencies from the local to federal levels. The continuing evolution of PFAS chemistries presents a challenge to the environmental monitoring, where ongoing development of targeted methods necessarily lags the discovery of new chemical compounds. There is a need, therefore, to have forward-looking methodologies that can detect emerging and unexpected compounds, monitor these species over time, and resolve details of their chemical structure to enable future work in human health. To this end, non-targeted analysis by high-resolution mass spectrometry offers a broad base detection approach that can be combined with almost any sample preparation scheme and provides significant capabilities for compound identification after detection. Herein, we describe a solid-phase extraction (SPE) based sample concentration method tuned for shorter chain and more hydrophilic PFAS chemistries, such as per fluorinated ether acids and sulfonates, and describe analysis of samples prepared in this fashion in both targeted and non-targeted modes. Targeted methods provide superior quantification when reference standards are available but are intrinsically limited to expected compounds when performing analysis. In contrast, a non-targeted approach can identify the presence of unexpected compounds and provide some information about their chemical structure. Information about chemical features can be used to correlate compounds across sample locations and track abundance and occurrence over time.

Here, we present a protocol for the sequential targeted quantification and non-targeted analysis of fluorinated compounds in water by mass spectrometry. This methodology provides quantitative levels of known fluorochemical compounds and identifies unknown chemicals in related samples with semi-quantitative estimates of their abundance.

利用目标筛选和非靶向筛选高分辨率质谱相结合的工作流程识别跨氟和多氟化学物种

Historical and emerging per- and polyfluoroalkyl substances (PFASs) have garnered significant interest from the public and government agencies from the ...

Using Caenorhabditis elegans for Studying Trans- and Multi-Generational Effects of Toxicants

Information about toxicities of chemicals are essential in their application and waste management. For chemicals at low concentrations, the long-term effects are very important in judging their consequences in the environment and on human health. In demonstrating long-term influences, effects of chemicals over generations in recent studies provide new insight. Here, we describe protocols for studying effects of chemicals over multiple generations using free-living nematode Caenorhabditis elegans. Two aspects are presented: (1) trans-generational (TG) and (2) multi-generational effect studies, the latter of which is separated to multi-generational exposure (MGE) and multi-generational residual (MGR) effect studies. The TG effect study is robust with a simple purpose to determine whether chemical exposure to parents can result in any residual consequences on offspring. After the effects are measured on parents, sodium hypochlorite solutions are used to kill the parents and keep the offspring so as to facilitate effect measurement on the offspring. The TG effect study is used to determine whether the offspring are affected when their parent is exposed to the pollutants. The MGE and MGR effect study is systematical used to determine whether continuous generational exposure can result in adaptive responses in offspring over generations. Careful pick-up and transfer are used to distinguish generations to facilitate effect measurement on each generation. We also combined protocols to measure locomotion behavior, reproduction, lifespan, biochemical and gene expression changes. Some example experiments are also presented to illustrate the trans- and multi-generational effect studies.

Using Caenorhabditis elegans for Studying Trans- and Multi-Generational Effects of Toxicants

Trans- and multi-generational effects of persistent chemicals are essential in judging their long-term consequences in the environment and on the human health. We provide novel detailed methods for studying trans- and multi-generational effects using free-living nematode Caenorhabditis elegans.

使用卡内哈布迪炎酶研究有毒物质的跨代和多代效应

Information about toxicities of chemicals are essential in their application and waste management. For chemicals at low concentrations, the long-term ...

Modeling the Size Spectrum for Macroinvertebrates and Fishes in Stream Ecosystems

The size spectrum is an inverse, allometric scaling relationship between average body mass (M) and the density (D) of individuals within an ecological community or food web. Importantly, the size spectrum assumes that individual size, rather than species&#8217; behavioral or life history characteristics, is the primary determinant of abundance within an ecosystem. Thus, unlike traditional allometric relationships that focus on species-level data (e.g., mean species&#8217; body size vs. population density), size spectra analyses are &#8216;ataxic&#8217; &#8211; individual specimens are identified only by their size, without consideration of taxonomic identity. Size spectra models are efficient representations of traditional, complex food webs and can be used in descriptive as well as predictive contexts (e.g., predicting responses of large consumers to changes in basal resources). Empirical studies from diverse aquatic ecosystems have also reported moderate to high levels of similarity in size spectra slopes, suggesting that common processes may regulate the abundances of small and large organisms in very different settings. This is a protocol to model the community-level size spectrum in wadable streams. The protocol consists of three main steps. First, collect quantitative benthic fish and invertebrate samples that can be used to estimate local densities. Second, standardize the fish and invertebrate data by converting all individuals to ataxic units (i.e., individuals identified by size, irrespective of taxonomic identity), and summing individuals within log2 size bins. Third, use linear regression to model the relationship between ataxic M and D estimates. Detailed instructions are provided herein to complete each of these steps, including custom software to facilitate D estimation and size spectra modeling.

This is a protocol to model the size spectrum (scaling relationship between individual mass and population density) for combined fish and invertebrate data from wadable streams and rivers. Methods include: field techniques to collect quantitative fish and invertebrate samples; lab methods to standardize the field data; and statistical data analysis.

对河流生态系统中巨脊椎动物和鱼类的大小谱进行建模

The size spectrum is an inverse, allometric scaling relationship between average body mass (M) and the density (D) of individuals within an ecological ...