资金支持由材料科学与技术能力中心（CCMX，NanoAir项目），瑞士国家科学基金会（项目139136），瑞士纳米科学研究所（Argovia，Project NanoFil）和瑞士生物能源研究能力中心（ SCCER BIOSWEET）。作者感谢Albert Schuler对TGA运作的支持，阿德莱德·卡尔布里 - 穆奇卡（Adelaide Calbry-Muzyka）则对这份手稿进行了评论。

RDD-SMPS-ICPMS设置<ol><li> RDD-SMPS-ICPMS设置的耦合策略 注意:为了耦合不同的仪器， 即 RDD，SMPS和ICPMS，并控制不同的气体流量，需要对仪器安排进行一些修改。耦合概念的主要步骤总结如下: <ol><li>使用内径/外径6.0 / 12.0 mm（碳浸硅胶管）的导电管连接不同的仪器部件。 </li><li>将旋转盘稀释器安装在气溶胶源和差分流动性分析仪或DMA之间，进行粒度分类。在DMA出口处将分类的气溶胶分成两部分。一个人将被冷凝颗粒计数器或CPC吸收。另一个引导到感应耦合等离子体质谱仪或ICPMS（ 图1 ）。 </li><li>使用质量流量控制器（MFC）以及过滤器，例如高效颗粒空气过滤器（HEPA），为RDD提供无颗粒稀释氩气。 </li><li>在RDD出口处添加另一个过滤器用于过量原始气体（Q RDD输出 ）。使用CPC时，不时检查所有使用过滤器的性能。 </li><li>使用另一个MFC和过滤器来调整引入到DMA中的鞘气流量（Q 鞘 ）。 </li><li>要调整DMA过量气体流量（Q DMA exc ），请在DMA出口处串联安装过滤器，MFC和真空泵。 </li><li>连接一个额外的MFC和过滤器，为CPC添加无颗粒空气（Q CPC空气 ），作为补充流量，以减少CPC消耗的分类气溶胶（Q CPC等级 ）。 注意:这是因为CPC主动吸入由约1升/分钟的临界孔和外部泵定义的流量。 ICP入口处的分类流量（Q ICP in ）是流量之间的差异（Q 类 ）和Q CPC类 。 </li></ol></li></ol> 2. RDD-SMPS-ICPMS测量协议注意:在调整SMPS-ICPMS参数之前，必须设置用于气溶胶发生器的流量。这里描述使用液体和固体样品的过程。 <ol><li> 气溶胶源示例 <ol><li>使用气溶胶发生器用于液体和悬浮液<ol><li>对于使用气溶胶发生剂用于悬浮液的实例，从市售的ZnO纳米粉末（ 例如公称直径为50nm）和聚丙烯酸作为纳米颗粒的稳定剂制备氧化锌（ZnO）悬浮液。稀释制备的悬浮液以获得约浓度的ZnO浓度。 30μg/ mL。选择这个浓度是因为随着所有的气体流动都会导致良好的ICPMS信号。 </li><li>对于第二次测量，制备钠水溶液浓度为200μg/ mL的氯化钠（NaCl）溶液。 <ol><li>首先，将悬浮液或溶液装入瓶子并将其安装在气溶胶发生器上。 </li></ol></li><li>使用气溶胶发生器从盐溶液或颗粒悬浮液中产生气溶胶，并从硅胶干燥器中的颗粒中除去水分。 <ol><li>将气溶胶发生器的压缩空气阀设置为略高于1巴。调整此结果导致扩散干燥器后面的气溶胶流量大约为1 L / min。最后，将干燥器的出口连接到RDD入口。 </li></ol></li></ol></li><li>使用热重量计或管式炉 注:作为将RDD-SMPS-ICPMS应用于热过程测量排放的示例，分析了氯化铜（CuCl 2 ）样品。使用两种气溶胶源，即TGA和管式炉。在这两种情况下，反应气体（ 例如 O <sub&gt; 2）与氩气混合以适当的比例，以防止成核和冷凝。在这项工作中，仅介绍了TGA实验的测量程序和代表性数据。 <ol><li>首先，去除空的TGA坩埚。称取50毫克CuCl 2粉末并将其放在坩埚中。 </li><li>将一个MFC用于反应气体（O 2 ）至约20 mL / min。 </li><li>将保护气体（氩气）的流量设置为约80 mL / min。在TGA出口处，加入约900 mL / min的氩气流，得到约1L / min的总流量（ 即 O 2流量，保护氩气和加入的氩气的总和）。如果使用RDD泵，请调整MFC以达到所需的流量。 </li><li>设置所需的温度程序（25°C，18 min，450°C，15 min）。 </li></ol></li></ol></li><li> 设置流量 注意:实现稳定运行RDD-SMPS-ICPMS设置，所有气体和气溶胶流量应如下所述仔细调整。在本节中，给出了用于调整RDD，SMPS和ICPMS的一组参数值的示例。另一组参数是可能的;但是程序将保持不变。所使用的流量缩写如图1所示 。在以下步骤中，使用流量计，例如流量校准器，在开始测量之前测量不同的气体和气溶胶流量。 <ol><li>首先将DMA入口处的氩鞘流量设置为3 L / min。 </li><li>将RDD加热块的温度设置为80°C，将蒸发管的温度设置为350°C。 </li><li>调整稀释氩的质量流量控制器，以便在旋转盘式稀释器（Q 样品 ）的出口处的稀释样品的流量获得0.6L / min。选择护套气体与样品气体的比例为0.6 / 3，以覆盖从约14至约340nm。 </li><li>然后，仔细调整过量气体质量流量控制器（Q DMA exc ）以达到0.6 L / min（Q 级 ）的分类气溶胶流量，与DMA入口（Q poly ）上稀释的多分散气溶胶的流速相同， 。 </li><li>接下来，将流量校准器放在DMA和CPC之间，并调整CPC补气量，以降低CPC吸入的分类气体的流量为0.18L / min。这相当于Q 类的 30％。 </li><li>检查分类气溶胶的剩余流量，以确保每分钟0.42升到ICPMS， 即分类气溶胶（Q 类 ）的70％。可以通过再次微调DMA过剩气体的MFC来校正该流量的轻微变化。 </li></ol></li><li> 设置SMPS软件 <ol><li>接下来，计算环境温度和压力下氩气的动态粘度和平均自由程度23 。 Ë在SMPS软件中使用这两个值。 </li><li>在SMPS软件中，将DMA扫描周期的上下扫描持续时间设置为150秒和30秒（ 即 1个DMA周期= 1次扫描= 180秒）。 </li><li>在SMPS软件中，将DMA最大电压设置为4.5 kV，以覆盖约14至约340 nm的PSD间隔。 注意:通常在气动SMPS中使用10 kV的最大电压。由于氩气相对于空气的介电强度较低，因此在本应用中应限制在较低的范围内，否则会导致电弧放电，导致仪器损坏和信号错误。 </li></ol></li><li> 设置ICPMS <ol><li>移除常规的液体样品引入系统，将干燥气溶胶直接引入ICPMS。在DMA出口的各个端口和ICPMS之间添加导电管。在氩基体中使用该管用于氙（Xe），浓度约为100 ppmv，以优化ICPMS等离子体并且在测量期间控制等离子体的稳定性。 </li><li>维持所有测量（ 例如 4 mL / min）的Xe流量常数，并调整ICPMS软件中的其他参数，包括ICP稀释气体和采样深度，以实现固定的Xe强度。 注意:主要的ICPMS调整参数如表1所示 。在每个测量之前要调谐的参数在最后一列中显示。 </li><li>设置SMPS和ICPMS采集时间以覆盖气溶胶测量的所需总持续时间（ 例如 ，对于10 SPMS扫描，将ICPMS采集时间设置为至少30分钟）。 </li><li>设置气体流量后，SMPS和ICPMS参数同时手动运行两台仪器。在TGA的情况下，在25℃下获取SMPS和ICPMS空白信号18分钟（6次扫描）。在悬浮液或液体样品的情况下，在6米的2次扫描期间获取空白信号将盘旋转速度设置为零。然后通过手动调整磁盘旋转速度将RDD的稀释系数设置为所需值。利用目前的配置，100％的转速对应于14.9的稀释系数。 </li></ol></li><li> 数据分析 注意:ICPMS测量每个m / z的每单位时间的离子强度（单位:每秒计数或cps）。该强度与分析物质量成比例。 SMPS数据表示基于由DMA背后的CPC确定的数量浓度的进入DMA的分类气溶胶（PSD n ）的加权PSD（单位:1 / cm 3 ）。为了比较ICP和SMPS信号，必须计算体积加权PSD（PSD v ）。应进行以下计算和更正: <ol><li>从ICPMS数据导出每个m / z的原始信号强度与时间的关系，以及由SMPS软件确定的PSD n作为pa的函数<html>直径（d p ）。从SMPS原始数据，输出粒径和相应的扫描时间。使用后者，以便将ICPMS测量时间与粒径相关联（见下文）。 注意:SMPS软件必须考虑到DMA出口处的气溶胶流分裂，只有30％的分类颗粒达到CPC。这可以通过将存储在单独的表中的计数效率值乘以因子为0.3来实现。 </li><li>由于所需的信息不是主要是RDD和DMA之间的颗粒浓度，而RDD入口处的浓度乘以RDD稀释因子， 即当前配置中的14.9。 </li><li>为了从原来的加权数字数据计算体积加权数据，将记录的PSD n浓度乘以测量颗粒的体积V（d P ）class ="xref"&gt; 6（V（d P ）=（π/ 6）∙d P 3 ）。 </li><li>通过从每个同位素的原始离子信号中减去背景信号来计算ICPMS净信号。然后，将净信号乘以逆单电荷概率1 / p +1 （d p ）以得到校正的ICP强度，其与DMA入口处的浓度大致成比例，因此在RDD入口处（假设没有颗粒损失在RDD入口和ICPMS或CPC入口之间）。 <ol><li>通过使用Wiedensohler近似24计算粒子携带一个元素正电荷的概率。对于由SMPS软件处理的SMPS数据，该充电概率的校正通常在软件中实现。 </li></ol></li><li>对于给定的SMPS扫描，在xy图中绘制SMPS粒子浓度或ICPMS强度作为粒径的函数。在稳定的情况下，使用相同类型的图表来呈现在几次扫描中平均的浓度或强度。 </li><li>对于一系列扫描，使用2D表面或3D图来绘制SMPS浓度或ICPMS强度作为直径和时间的函数。在热处理的情况下，如果使用温度程序，则将时间替换为相应的温度值。 注意:此外，使用MATLAB或Igor Pro等计算软件可以自动使用ICPMS和SMPS数据进行此类绘图所需的计算，从而可以在短时间内获得稳健的最终结果。 </li></ol></li></ol>

<ol>
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A., Willeke, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Aerosol Measurement: Principles, Techniques, and Applications. , 18-19 (2011).</li><li>Wiedensohler, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+approximation+of+the+bipolar+charge+distribution+for+particles+in+the+submicron+size+range.">An approximation of the bipolar charge distribution for particles in the submicron size range.</a> J Aerosol Sci. 19 (3), 387-389 (1988).</li><li>Ludwig, C., Wochele, J., J&#246;rimann, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measuring+evaporation+rates+of+metal+compounds+from+solid+samples.">Measuring evaporation rates of metal compounds from solid samples.</a> Anal Chem. 79 (7), 2992-2996 (2007).</li><li>Kovacs, R., Nishiguchi, K., Utani, K., G&#252;nther, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+direct+atmospheric+sampling+for+laser+ablation-inductively+coupled+plasma-mass+spectrometry.">Development of direct atmospheric sampling for laser ablation-inductively coupled plasma-mass spectrometry.</a> J. Anal. At. Spectrom. 25 (2), 142-147 (2010).</li></ol>

作者宣称没有竞争的经济利益。

与目前现有的气溶胶分析方法（如粒度分析仪）相比，RDD-SMPS-ICPMS组合不仅能够同时获得化学和尺寸信息，而且时间分辨的ICPMS信号也允许确定每个要素在总体PSD中的贡献。然而，只有直径小于500nm的颗粒可以通过目前的氩气操作的SMPS-ICPMS来测量。此外，对于气溶胶颗粒的完整表征，需要其他离线技术来确定其他性质，包括形态和分子结构。 NaCl测量是一个简单的例子，显示了使用耦合的SMPS-ICPMS系统能够很好地控制/监测稳态过程。该设置也可以用于在线分析工具的实验中，以揭示不同实验参数对生成部分的性质的影响克莱斯。颗粒尺寸，颗粒或元素浓度的任何变化，例如在CuCl 2样品热处理的情况下，都可以通过SMPS-ICPMS进行在线跟踪。 另一方面，SMPS-ICPMS组合不仅可以测量，还可以区分气体和颗粒物质。实际上，与颗粒物相关的信号的部分可以容易地与气体化合物的区别，因为后者的ICPMS信号覆盖整个尺寸范围，并且不遵循与颗粒相关的信号的分布形状。这是由于SMPS扫描对气态物质没有影响，ICPMS测量给定同位素的总强度。这种行为通过测量Cl来证明，其不仅作为颗粒而且作为气体物质蒸发（ 图4D-4E ）。实际上，热力学计算表明在氧化条件下在约450℃下，CuCl 2作为Cl 2气体和作为可冷凝物质CuCl 2 ，Cu 3 Cl 3和Cu 4 Cl 4蒸发（数据未显示）。 此外，使用没有SMPS的ICPMS可以测量源自气态或微粒物种的总体ICPMS信号。使用这种排列来测量CuCl 2蒸发（ 图4F ），例如，显示蒸发的Cu和Cl之间的化学计量在加热期间不会改变，因为类似的信号形状。此外，通过在RDD出口处安装颗粒过滤器，可以通过相同的设置专门测量气态物质。 在测量协议中有两个关键点。一方面，较小的ICPMS强度曲线，与PSD v在较大的粒径范围（ 例如 ，图2B）可以通过数据评估程序（正在进行的工作）中尚未实现多粒子收费的考虑来解释。当单电荷校正在测量小颗粒（高达200nm）时，SMPS和ICPMS数据之间具有良好的相关性，应建立并实施对大颗粒上的多次电荷的校正，以提高200以上颗粒的结果信息的质量纳米。这种效应的另一解释可能是较大的颗粒在等离子体中不完全分解和离子化。 第二个关键点是选择适当的RDD稀释因子。实际上，像液体样品的分析一样，不同同位素的ICPMS强度水平取决于相应的灵敏度。例如，Cu信号比Cl高约三个数量级。因此，气溶胶稀释的适当值必须是考虑到测量元件的ICPMS灵敏度。这提出了气溶胶多元素分析的局限性。然而，如果已知气溶胶生成过程，则在相同的实验中可以改变气溶胶稀释值。例如，在产生低粒子量的期间，可以降低稀释倍数。然而，应避免将高粒度负载的气溶胶送入DMA，以保护CPC和ICPMS仪器。总之，取决于采样的气溶胶，应该找到RDD稀释，基质负载和ICPMS对感兴趣的同位素敏感性之间的妥协。此外，SMPS-ICPMS设置的时间分辨率受到SMPS扫描持续时间的限制，SMPS扫描持续时间在几分钟的范围内。然而，对于固定或窄范围的粒子尺寸，可以提高时间分辨率。 仍然需要开发整体设置的量化方法（正在进行中）K）。对于热处理，TGA可用作定量的工具25 。液体或悬浮液的定量可以使用适当的标准溶液进行。此外，设计用于氩气的再循环概念，用空气操作DMA并将其交换到氩气 - 例如通过气体交换装置26 - 将允许使用更高的DMA电压并因此使得测量的颗粒范围的增加。最后自动化不同参数的设置，并将SMPS和ICPMS的需求并入关于操作条件的单一概念中，将大大降低测量协议的步骤。这些步骤有助于使SMPS-ICPMS成为强大的在线设置，用于定量或定性分析从液体，悬浮液或排放源产生的不同种类的气溶胶。

在许多领域，气溶胶和悬浮液中颗粒的表征 - 包括测定化学成分和尺寸分布 - 是一个重要的问题。用于确定颗粒性质的各种分析技术用于不同的环境，工业和研究应用，如测量/监测空气传播或燃烧发射的颗粒，表征合成工程纳米物体，以及研究其健康和环境影响。 传统的悬浮液颗粒和颗粒的尺寸信息通常由不同的颗粒尺寸分析仪分析，如气动粒子测定仪（APS），动态光散射装置（DLS）或扫描流动性粒度仪（SMPS） 1,2 ， 3，4，5 。该后者完善的气溶胶测量工具由差分流动分析仪（DMA）和冷凝颗粒计数器（CPC）两部分组成。两种仪器都是串联安装的。第一种允许通过改变两个电极6之间的电压，根据气溶胶颗粒在气流中的迁移率直径进行分类。在CPC中，进入纳米颗粒作为凝结核，形成"大"液滴，然后进行光学计数。 SMPS输出数据表示关于测量的粒子的大小分辨数量信息，并且作为粒子分布（PSD）给出。 另一方面，悬浮液中气体颗粒和颗粒的化学特性通常在离线状态下进行7 。在分析之前需要适当的收集和样品制备程序。这样离线研究通常包括应用光谱技术，如电感耦合等离子体质谱（ICPMS）。这是液体样品的元素和痕量元素分析中具有非常高的灵敏度和低检测限的确定方法8 。在ICPMS中，氩等离子体用于将引入的样品干燥并分解成原子离子。然后根据其质荷比（m / z）对其进行分类，最后以模拟或脉冲模式计数。除了液体样品，这种技术也用于气体和颗粒分析。例如，气体可以直接引入ICPMS并分析9,10,11 。在形态分析中，使用耦合到ICPMS的气相色谱仪（GC）分离和检测挥发性化合物12 。 ICPMS被进一步开发为所谓的单粒子ICPMS（sp-ICPMS），以便于使用<html>使悬浮液13,14中的单分散颗粒变细。使用其它表面和/或体分析技术来实现完整的表征，和/或获得关于颗粒特性的更多信息。诸如扫描电子显微镜（SEM）和透射电子显微镜（TEM）的成像技术被广泛用于该目的15,16,17 。 为了同时获得时间分辨的化学和尺寸信息，可以在一个设置18中组合两种不同的分析技术，例如SMPS和等离子体光谱技术。这种在线测量概念可以避免与采样，准备和离线分析过程相关的问题。 Hess等人报道了以前尝试开发这种组合设置的简要概述。"xref"&gt; 19。 在这项工作中，给出了组合的SMPS-ICPMS测量布置和程序的详细描述。旋转盘稀释器（RDD）用作介绍界面。这种连字技术的发展和三个应用研究可以在文献19,20,21中找到。 Hess et al。 2 0显示，开发的SMPS-ICPMS仪器的性能与单独的最先进系统的性能相当。这项研究是以前的出版物19,20,21的补充，并给出了一个描述如何使用该设置的实验室实践。来自两个不同来源的气溶胶的实例应用不久将被描述，以显示耦合s的通用性ystem。 在描述测量协议之前，值得总结单个组件和连字符设置的耦合策略。更详细的描述可以在其他地方找到。耦合设置的主要组成部分是:气溶胶源，RDD，DMA，CPC和ICPMS。 为了从悬浮液或液体溶液中产生干燥的气溶胶颗粒，使用配有喷嘴和硅胶干燥器的气溶胶发生器。详细说明可以在其他地方找到。为了研究热过程，使用热重分析仪TGA（或管式炉）。 RDD用于气溶胶样品引入22 。它由一个装有两个通道的可加热钢块和一个具有多个空腔的旋转盘组成。通道用稀释气体和来自气溶胶的原始气溶胶冲洗资源。根据气流和盘旋转速度，向稀释气体中加入一定量的原始气溶胶，得到规定的稀释比。由于ICPMS的低耐受性，氩气被用作稀释气体。但是，为了避免电弧放电，DMA电压限制应设置为低于气动DMA的电压限制。由于RDD出口处的稀释样品气溶胶的流动可以独立于原始气溶胶流量进行精确控制，因此RDD采样概念可用于不同的气溶胶源。在RDD和SMPS之间安装加热管（高达400°C），以蒸发挥发性颗粒，和/或进一步稀释气溶胶。当处理含有机物的样品时，需要这一步骤才能实现良好的再现性。然而，这也可能引发化学反应。例如，热解开始于低得多的温度下，不仅可以分解颗粒，而且还会引起一些化学反应。 SMPS使用i这个工作包括DMA管（类似于长DMA;参见材料表）和商业CPC。在进入DMA之前，稀释的气溶胶必须通过称为气溶胶中和剂的放射源，以建立已知的电荷平衡（假定为玻尔兹曼电荷分布） 6 。然后通过改变给定DMA护套和气溶胶气体流的电压，根据其迁移率直径来分类颗粒。在DMA出口处的流量分流完成，使得30％的气溶胶被引导到CPC，另外70％被引导到ICPMS。分类颗粒的数量浓度由CPC确定。通过商业ICPMS仪器分析另一个气溶胶部分，允许对气溶胶负载的颗粒进行元素分析。由于没有研究液体，所以常规的样品引入系统被去除，DMA出口直接连接到ICPMS。第二个RDD和另一个航空商业SMPS用作参考仪器来验证由SMPS-ICPMS耦合设置测量的PSD。 RDD-SMPS参考系统连接到耦合系统的RDD的原始气溶胶出口。

<table><tbody><tr><td>ICPMS</td><td>Agilent Technologies, USA</td><td>7700x</td><td>Inductively Coupled&lt;br/&gt; Plasma Mass Spectrometer</td></tr><tr><td>DMA tube</td><td></td><td></td><td>similar to 3081 long DMA&lt;br/&gt; from TSI</td></tr><tr><td>Aerosol Neutralizer</td><td>TSI Inc., USA</td><td></td><td>85Kr radiation source</td></tr><tr><td>CPC</td><td>TSI Inc., USA</td><td>3010</td><td>Condensation Particle&lt;br/&gt; Counter</td></tr><tr><td>RDD</td><td>Matter Aerosol AG, Switzerland</td><td>MD193E</td><td>Rotating Disk Diluter;</td></tr><tr><td>Evaporation Tube</td><td>Matter Aerosol AG, Switzerland</td><td>ASET 15-1</td><td>Heated Tube</td></tr><tr><td>Aerosol Generator</td><td>Topas GmbH, Germany</td><td>ATM 220</td><td>aerosol generator</td></tr><tr><td>Silica Gel Drier</td><td>Topas GmbH, Germany</td><td>DDU570/H</td><td>silica gel diffusion drier</td></tr><tr><td>TGA</td><td>Mettler-Toledo Internat. Inc., CH</td><td>TGA/DCS1</td><td>Thermogravimetric analyzer</td></tr><tr><td>Gilibrator 2</td><td>Sensidyne, USA</td><td></td><td>primary flow calibrator</td></tr><tr><td>MFC</td><td>Sierra Instruments Inc., USA</td><td>Smart-Trak 50</td><td>mass flow controller</td></tr><tr><td>MFC</td><td>Brooks Instrument, Netherlands</td><td>4850</td><td>mass flow controller</td></tr><tr><td>MFC</td><td>Bronkhorst AG, Netherlands</td><td>F-201C-FAC-33-V</td><td>mass flow controller</td></tr><tr><td>In-Line Filter</td><td>Headline Filters, UK</td><td>DIF-LN30</td><td>disposable in-line filter</td></tr><tr><td>HEPA Filter</td><td>MSA (Mine Safety Appliances), USA</td><td>H cartridge #95302</td><td>High-Efficiency Particulate&lt;br/&gt; Air&lt;br/&gt; &amp;nbsp;</td></tr><tr><td>Conductive tubing</td><td>Advanced Polymers Ltd&lt;br/&gt; Worthing, UK.</td><td></td><td>carbon impregnated silicone&lt;br/&gt; tubing, inner/outer&lt;br/&gt; diameters 6.0/12.0 mm</td></tr><tr><td>&lt;strong&gt;Name&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog number&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>ZnO</td><td>Auer-Remy</td><td>5810MR, 1314-13-2</td><td>Nanopowder, 50 nm</td></tr><tr><td>NaCl</td><td>Merck</td><td>106406</td><td>Powder (&gt;99.99%)</td></tr><tr><td>CuCl&lt;sub&gt;2&lt;/sub&gt;</td><td>Merck</td><td>102733</td><td>Powder (&gt;99.0%)</td></tr><tr><td>Poly-Acrylic Acid</td><td>SigmaAldrich</td><td>535931</td><td>solution (50 wt. % in H&lt;sub&gt;2&lt;/sub&gt;O)</td></tr></tbody></table>

a practical guide on coupling a scanning mobility sizer and inductively coupled plasma mass spectrometer (smps-icpms)

有各种各样的分析方法可用于表征气溶胶和悬浮液中的颗粒。适当技术的选择取决于要确定的性质。在许多领域，关于粒度和化学成分的信息是非常重要的。在气溶胶技术中，气相色谱颗粒的粒度分布在线确定，但在合适的取样和准备程序之后，它们的元素组成通常在线下分析。为了在线和同时获取这两种类型的信息，最近开发了一个连字符设置，包括扫描移动粒子测量仪（SMPS）和电感耦合等离子体质谱仪（ICPMS）。这允许首先根据其迁移率直径对颗粒进行分类，然后并行确定它们的数量浓度和元素组成。旋转盘式稀释器（RDD）用作引入系统，提供更多的功能关于使用不同气溶胶源的灵活性。在这项工作中，提供了一个实用指南，介绍了建立该仪器的不同步骤，以及如何使用该分析工具。在由a）盐溶液，b）悬浮液和c）通过热过程发射的三种不同气溶胶的实例测量中证明了这种连字技术的通用性。

在第一个例子中，该设置被用作测量ZnO悬浮液产生的在线粒子的工具（ 图2 ）。 如图2A-2B所示 ，当与PSD n相比时，PSD v出现朝向更大的颗粒移动。此外，在大粒径下，ICPMS强度曲线略低于由SMPS检测的曲线。在第二实施例中，使用相同的气溶胶发生器从NaCl水溶液（200μg/ mL）生成颗粒（ 图 3A-3C ）。 ICPMS和SMPS信号不随时间呈现显着变化，并且在整个测量期间钠的时间分辨信号与PSD v良好相关。与上述实施例中的Zn不同，Na具有相对高的ICPMS背景信号，导致比由SMPS记录的浓度更高的信号。如在ZnO悬浮液样品，PSD n的模式位于比PSD v更低的粒径。由于生成的颗粒是NaCl颗粒，所以Cl信号的行为与Na相似，并且与体积相关的SMPS数据很好地相关（数据未显示）。 在最后一个例子中，介绍了使用TGA热处理CuCl 2样品的结果。 图4A示出了在TGA加热开始时（在时间轴上约21分钟， 即在第七次 SMPS扫描开始时），对于低达20nm的粒子记录的PSD n 。此后，当温度保持恒定时，PSD n中的颗粒浓度达到稳定状态，颗粒的尺寸范围在60至250nm之间。在第11 次 SMPS扫描后（在时间轴上约30分钟），粒径观察到略微增加。精读对于PSD v （ 图4B ），不同粒径的贡献与PSD n的贡献大不相同，PSD v主要在150和330 nm之间变高。 图3C所示的ICP的ICPMS信号与PSD v 。 图4D-4E分别显示上下扫描期间的校正和原始35 Cl强度。在加热阶段的起点之后，除了对应于氯物质颗粒的强度之外，测量恒定Cl强度覆盖粒度范围（在时间间隔18至33分钟内， 即从第7到第11 次 SMPS扫描）。这是由于Cl气态物质的蒸发。氯颗粒以与铜相同的尺寸范围记录，即直径在150nm以上的颗粒。在没有S的情况下进行使用相同样品（CuCl 2 ）的另一个实验并且仅使用TG-RDD-ICPMS设置。在此测量非分类气溶胶颗粒的ICPMS信号（图4F）。与SMPS-ICPMS的情况类似，可以观察到上次扫描中的两个信号（Cl和Cu）的增加。 在这项工作中报告的结果证明了具有不同气溶胶源的耦合的SMPS-ICPMS系统的通用性。在实施例中，Cu和PSD v的时间分辨ICPMS信号之间的相关性是显而易见的。对于装载有不同粒子的气溶胶，每个元素在整个PSD v中的贡献由ICPMS信号确定。此外，NaCl的实例表明，保持实验条件恒定导致稳态时间分辨信号。 SMPS-ICPMS设置允许监测产生的气溶胶的元素和/或尺寸浓度的任何变化。例如，PSD的较高信号n在CuCl 2实验中（ 图4C ）可能由加热过程的突然启动引起。同时，最终扫描期间SMPS和ICPMS信号的增加可以通过随着时间的推移CuCl 2样品的温度梯度的变化来解释，这使得材料的总量达到蒸发温度。最后，考虑到SMPS输出数据，PSD v中的浓度朝向比PSD n更大的粒度移动。这是因为信号与粒径的3 次幂相乘以将PSD n转换为PSD v ，导致体积中的大颗粒对数量方面的加权更强。 <img alt="图1" src="/files/ftp_upload/55487/55487fig1.jpg" /> 图1:RDD-SMPS-ICPMS设置中不同仪器部件的耦合策略。 </strong&gt;命名:Q 样品 :来自气溶胶发生器的流量; Q 稀释 :RDD稀释氩气流，Q RDD出 :原始气溶胶流出RDD ; Q poly :在DMA入口处稀释的多分散气溶胶的流动; Q 鞘 :DMA鞘气流; Q 级 :DMA出口处分类气溶胶流; Q DMA exc :DMA气体过量流; Q 中共阶层 :Q 级小学部分进入中共; 中共空气 : 中共的额外空气流量; Q CPC :总流入CPC; Q ICP :Q 级导入ICPMS的分数; Q e :氙流; MFC:质量流量控制器。 <a href="https://ecsource-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/55487/55487fig1large.jpg" target="_blank">请点击此处查看此图的较大版本。</a> <img alt="图2" src="/files/ftp_upload/55487/55487fig2.jpg" /> <html> 图2:ZnO悬浮液的SMPS-ICPMS数据。 （ A ）基于数字的PSD（PSD n ），由SMPS记录。 （ B ）通过ICPMS检测相应的基于体积的PSD（PSD v ）和校正的66 Zn信号。三个信号是超过4次SMPS扫描的平均值。 <a href="https://ecsource-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/55487/55487fig2large.jpg" target="_blank">请点击此处查看此图的较大版本。</a> <img alt="图3" src="/files/ftp_upload/55487/55487fig3.jpg" /> 图3:NaCl溶液测量的SMPS-ICPMS数据。 （ A ） 23 Na的ICP校正信号。 （ B ）PSD v 。 （ C ）相应的PSD n 。将SMPS浓度和ICPMS强度绘制为直径和时间的函数。55487fig3large.jpg"target ="_ blank"&gt;请点击此处查看此图的较大版本。 <img alt="图4" src="/files/ftp_upload/55487/55487fig4.jpg" /> 图4:使用TGA测量CuCl 2蒸发的SMPS-ICPMS数据。 （ A ）PSD的2D图2D（2D）PSD的2D图（ C ） 63 Cu ICPMS信号的2D图。 （ D ） 35 CI ICPMS信号的2D图。 （ E ）未校正的原始35 Cl ICPMS信号与时间。 （ F ）使用TG-RDD-ICPMS设置（无SMPS）在CuCl 2热处理过程中记录的65 Cu和35 Cl的ICPMS信号。在两个实验（有和没有SMPS）中，在启动和保持加热周期（15分钟）之前，测量25℃下的空白信号约为18分钟（6次SMPS扫描）76℃。 SMPS-ICPMS信号的记录与TGA信号的同时开始，并且在关闭之后停止1次扫描（导致总共12次SMPS扫描）。 <a href="https://ecsource-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/55487/55487fig4large.jpg" target="_blank">请点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> 参数 </td><td> 值 </td><td> 要调整 </td></tr><tr><td>功率</td><td> 1350 W </td><td>是</td></tr><tr><td> ICP稀释气体（氩） </td><td> 0.58升/分钟</td><td>是</td></tr><tr><td>采样深度</td><td> 8毫米</td><td>是</td></tr><tr><td>碰撞气体</td><td> 2 mL / min </td><td>是（对于相同的测量集，调整后不改变该值） </td></tr><tr><td> INTEGRation时间</td><td>每个同位素0.2 s </td><td>是的，如果ICP时间分辨率应该改变</td></tr><tr><td> e流</td><td> 4 mL / min </td><td>否（保持相同的ICP灵敏度） </td></tr></tbody></table> 表1:用于RDD-SMPS-ICPMS测量气溶胶颗粒的主ICPMS参数的典型设置。

Watch this Scientific Journal Video about A Practical Guide on Coupling a Scanning Mobility Sizer and Inductively Coupled Plasma Mass Spectrometer SMPS-ICPMS at JoVE.com

A Practical Guide on Coupling a Scanning Mobility Sizer and Inductively Coupled Plasma Mass Spectrometer SMPS-ICPMS

在这项工作中，提供了一个实用指南，描述了建立SMPS和ICPMS系统耦合的不同步骤，以及如何使用它们。介绍了三个描述性例子。

耦合扫描流动性测定仪和电感耦合等离子体质谱仪（SMPS-ICPMS）的实用指南

A large variety of analytical methods are available to characterize particles in aerosols and suspensions. The choice of the appropriate technique depends ...

a-practical-guide-on-coupling-scanning-mobility-sizer-inductively

Universidad San Sebastian

Research

JoVE Journal

Chemistry

A Practical Guide on Coupling a Scanning Mobility Sizer and Inductively Coupled Plasma Mass Spectrometer (SMPS-ICPMS)

10.7K 次观看.  Paul Scherrer Institute. 在这项工作中，提供了一个实用指南，描述了建立SMPS和ICPMS系统耦合的不同步骤，以及如何使用它们。介绍了三个描述性例子。 

视频: A Practical Guide on Coupling a Scanning Mobility Sizer and Inductively Coupled Plasma Mass Spectrometer SMPS-ICPMS

Analysis of Volatile and Oxidation Sensitive Compounds Using a Cold Inlet System and Electron Impact Mass Spectrometry

This video presents a protocol for the mass spectrometrical analysis of volatile and oxidation sensitive compounds using electron impact ionization. The analysis of volatile and oxidation sensitive compounds by mass spectrometry is not easily achieved, as all state-of-the-art mass spectrometric methods require at least one sample preparation step, e.g., dissolution and dilution of the analyte (electrospray ionization), co-crystallization of the analyte with a matrix compound (matrix-assisted laser desorption/ionization), or transfer of the prepared samples into the ionization source of the mass spectrometer, to be conducted under atmospheric conditions. Here, the use of a sample inlet system is described which enables the analysis of volatile metal organyls, silanes, and phosphanes using a sector field mass spectrometer equipped with an electron impact ionization source. All sample preparation steps and the sample introduction into the ion source of the mass spectrometer take place either under air-free conditions or under vacuum, enabling the analysis of compounds highly susceptible to oxidation. The presented technique is especially of interest for inorganic chemists, working with metal organyls, silanes, or phosphanes, which have to be handled using inert conditions, such as the Schlenk technique. The principle of operation is presented in this video.

This video presents a protocol for the mass spectrometrical analysis of volatile and oxidation sensitive compounds using electron impact ionization. The presented technique is especially of interest for inorganic chemists, working with metal organyls, silanes, or phosphanes which have to be handled using inert conditions, such as the Schlenk technique.

挥发和氧化敏感的化合物使用冷进气系统和电子轰击质谱分析

This video presents a protocol for the mass spectrometrical analysis of volatile and oxidation sensitive compounds using electron impact ionization. The ...

科研

化学

Quantitative and Qualitative Method for Sphingomyelin by LC-MS Using Two Stable Isotopically Labeled Sphingomyelin Species

We present a method of analyzing sphingomyelin (SM) qualitatively and quantitatively by liquid chromatography-electrospray Ionization-tandem mass spectrometry (LC-ESI-MS/MS). SM is a common sphingolipid composed of a phosphorylcholine and a ceramide as the hydrophilic and hydrophobic component, respectively. A number of SM species are present in mammalian cells due to a variety in the sphingoid long chain base (LCB) and an N-acyl moiety in the ceramide. In this report, we show a method of estimating the number of carbon and double bonds in a LCB and an N-acyl moiety based on their corresponding product ions in MS/MS/MS (MS3) experiments. In addition, we present a quantitative analysis method for SM using two stable isotopically labeled SM species, which facilitates determining the range used in SM quantitation. The present method will be useful in characterizing a variety of SM species in biological samples and industrial products such as cosmetics.

Here, we present a protocol to quantify and qualify each sphingomyelin species using multiple reaction monitoring and MS/MS/MS mode, respectively.

用两个稳定 Isotopically 标记鞘磷脂种鞘磷脂的定量和定性方法

We present a method of analyzing sphingomyelin (SM) qualitatively and quantitatively by liquid chromatography-electrospray Ionization-tandem mass ...

生物化学

Versatile Dual-Inlet Sample Introduction System for Multi-Mode Single Particle Inductively Coupled Plasma Mass Spectrometry Analysis and Validation

Metal-containing nanoparticles (NP) can be characterized with inductively coupled plasma mass spectrometers (ICP-MS) in terms of their size and number concentration by using the single-particle mode of the instrument (spICP-MS). The accuracy of measurement depends on the setup, operational conditions of the instrument and specific parameters that are set by the user. The transport efficiency of the ICP-MS is crucial for the quantification of the NP and usually requires a reference material with homogenous size distribution and a known particle number concentration.
Currently, NP reference materials are available for only a few metals and in limited sizes. If particles are characterized without a reference standard, the results of both size and particle number may be biased. Therefore, a dual-inlet setup for characterizing nanoparticles with spICP-MS was developed to overcome this problem. This setup is based on a conventional introduction system consisting of a pneumatic nebulizer (PN) for nanoparticle solutions and a microdroplet generator (&#181;DG) for ionic calibration solutions. A new and flexible interface was developed to facilitate the coupling of &#181;DG, PN and the ICP-MS system. The interface consists of available laboratory components and allows for the calibration, nanoparticle (NP) characterization and cleaning of the arrangement, while the ICP-MS instrument is still running.
Three independent analysis modes are available for determining particle size and number concentration. Each mode is based on a different calibration principle. While mode I (counting) and mode III (&#181;DG) are known from the literature, mode II (sensitivity), is used to determine the transport efficiency by inorganic ionic standard solutions only. It is independent of NP reference materials. The &#181;DG based inlet system described here guarantees superior analyte sensitivities and, therefore, lower detection limits (LOD). The size dependent LODs achieved are less than 15 nm for all NP (Au, Ag, CeO2) investigated.

Here we provide a protocol for the use of a dual-inlet system for single particle inductively coupled mass spectrometry which allows for a standard independent nanoparticle characterization.

Metal-containing nanoparticles (NP) can be characterized with inductively coupled plasma mass spectrometers (ICP-MS) in terms of their size and number ...

Using a Cyclic Ion Mobility Spectrometer for Tandem Ion Mobility Experiments

Accurate characterization of chemical structures is important to understand their underlying biological mechanisms and functional properties. Mass spectrometry (MS) is a popular tool but is not always sufficient to completely unveil all structural features. For example, although carbohydrates are biologically relevant, their characterization is complicated by numerous levels of isomerism. Ion mobility spectrometry (IMS) is an interesting complement because it is sensitive to ion conformations and, thus, to isomerism. 
Furthermore, recent advances have significantly improved the technique: the last generation of Cyclic IMS instruments offers additional capabilities compared to linear IMS instruments, such as an increased resolving power or the possibility to perform tandem ion mobility (IMS/IMS) experiments. During IMS/IMS, an ion is selected based on its ion mobility, fragmented, and reanalyzed to obtain ion mobility information about its fragments. Recent work showed that the mobility profiles of the fragments contained in such IMS/IMS data can act as a fingerprint of a particular glycan and can be used in a molecular networking strategy to organize glycomics datasets in a structurally relevant way. 
The goal of this protocol is thus to describe how to generate IMS/IMS data, from sample preparation to the final Collision Cross Section (CCS) calibration of the ion mobility dimension that yields reproducible spectra. Taking the example of one representative glycan, this protocol will show how to build an IMS/IMS control sequence on a Cyclic IMS instrument, how to account for this control sequence to translate IMS arrival time into drift time (i.e., the effective separation time applied to the ions), and how to extract the relevant mobility information from the raw data. This protocol is designed to clearly explain the critical points of an IMS/IMS experiment and thus help new Cyclic IMS users perform straightforward and reproducible acquisitions.

Ion mobility spectrometry (IMS) is an interesting complement to mass spectrometry for the characterization of biomolecules, notably because it is sensitive to isomerism. This protocol describes a tandem IMS (IMS/IMS) experiment, which allows the isolation of a molecule and the generation of the mobility profiles of its fragments.

使用循环离子淌度光谱仪进行串联离子淌度实验

Accurate characterization of chemical structures is important to understand their underlying biological mechanisms and functional properties. Mass ...

<meta charset="utf8"></head><body>使用 LC-IMS-MS 增强麦角生物碱的异构体分离

Detection of Regulated Ergot Alkaloids in Food Matrices by Liquid Chromatography-Trapped Ion Mobility Spectrometry-Time-of-Flight Mass Spectrometry

Ion mobility mass spectrometry (IMS) acts as an additional separation dimension when integrated into liquid chromatography-mass spectrometry (LC-MS) workflows. LC-IMS-MS methods provide higher peak resolution, enhanced separation of isobaric and isomeric compounds, and improved signal-to-noise ratio (S/N) compared to traditional LC-MS methods. IMS provides another molecular characteristic for the identification of analytes, namely the collision cross section (CCS) parameter, reducing false positive results. Therefore, LC-IMS-MS methods address important analytical challenges in the field of food safety (i.e., detection of compounds at trace levels in complex food matrices and unambiguous identification of isobaric and isomeric molecules).
Ergot alkaloids (EAs) are a family of mycotoxins produced by fungi that attack a wide variety of grass species, including small grains such as rye, triticale, wheat, barley, millet, and oats. Maximum levels (MLs) of these mycotoxins have been established in several foodstuffs, as detailed in the Commission Regulation EC/2023/915. This new legislation includes six main EAs and their corresponding epimers, so an efficient methodology is required to properly distinguish these isomeric molecules considering their co-occurrence.
Therefore, the goal of this protocol is to show how the integration of IMS in LC-MS workflows contributes to the separation of isomeric EAs, enhancing the selectivity of the analytical method. Additionally, it illustrates how the generation of CCS libraries through the characterization of analytical standards provides higher confidence for the identification of mycotoxins. This protocol is designed to clearly explain the benefits of implementing IMS in food safety, taking as an example the determination of EAs in cereals. A QuEChERS-based extraction followed by an LC-trapped ion mobility spectrometry (TIMS)-MS analysis provided limits of quantification ranging from 0.65 to 2.6 ng/g with acceptable accuracy (although low recovery for ergotaminine) at 1.5x, 1x, and 0.5x the ML and exhibited a negligible matrix effect.

<meta charset="utf8"></head><body>通过液相色谱-捕获离子迁移谱-飞行时间质谱法检测食品基质中受管制的麦角生物碱

This protocol presents a validated liquid chromatography-ion mobility-high resolution mass spectrometry method to determine the presence of ergot alkaloids in food in compliance with the recently released Commission Regulation (EU) 2023/915.

通过液相色谱-捕获离子迁移谱-飞行时间质谱法检测食品基质中受管制的麦角生物碱

Ion mobility mass spectrometry (IMS) acts as an additional separation dimension when integrated into liquid chromatography-mass spectrometry (LC-MS) ...

Imaging Metals in Brain Tissue by Laser Ablation - Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS)

Metals are found ubiquitously throughout an organism, with their biological role dictated by both their chemical reactivity and abundance within a specific anatomical region. Within the brain, metals have a highly compartmentalized distribution, depending on the primary function they play within the central nervous system. Imaging the spatial distribution of metals has provided unique insight into the biochemical architecture of the brain, allowing direct correlation between neuroanatomical regions and their known function with regard to metal-dependent processes. In addition, several age-related neurological disorders feature disrupted metal homeostasis, which is often confined to small regions of the brain that are otherwise difficult to analyze. Here, we describe a comprehensive method for quantitatively imaging metals in the mouse brain, using laser ablation - inductively coupled plasma - mass spectrometry (LA-ICP-MS) and specially designed image processing software. Focusing on iron, copper and zinc, which are three of the most abundant and disease-relevant metals within the brain, we describe the essential steps in sample preparation, analysis, quantitative measurements and image processing to produce maps of metal distribution within the low micrometer resolution range. This technique, applicable to any cut tissue section, is capable of demonstrating the highly variable distribution of metals within an organ or system, and can be used to identify changes in metal homeostasis and absolute levels within fine anatomical structures.

Imaging Metals in Brain Tissue by Laser Ablation - Inductively Coupled Plasma - Mass Spectrometry LA-ICP-MS

Quantitatively mapping metals in tissue by laser ablation - inductively coupled plasma - mass spectrometry (LA-ICP-MS) is a sensitive analytical technique that can provide new insight into how metals participate in normal function and disease processes. Here, we describe a protocol for quantitatively imaging metals in thin sections of mouse neurological tissue.

在脑组织成像金属激光剥蚀 - 电感耦合等离子体 - 质谱法（LA-ICP-MS）

Metals are found ubiquitously throughout an organism, with their biological role dictated by both their chemical reactivity and abundance within a ...

医学

Applications of the Single-probe: Mass Spectrometry Imaging and Single Cell Analysis under Ambient Conditions

Mass spectrometry imaging (MSI) and in-situ single cell mass spectrometry (SCMS) analysis under ambient conditions are two emerging fields with great potential for the detailed mass spectrometry (MS) analysis of biomolecules from biological samples. The single-probe, a miniaturized device with integrated sampling and ionization capabilities, is capable of performing both ambient MSI and in-situ SCMS analysis. For ambient MSI, the single-probe uses surface micro-extraction to continually conduct MS analysis of the sample, and this technique allows the creation of MS images with high spatial resolution (8.5 &#181;m) from biological samples such as mouse brain and kidney sections. Ambient MSI has the advantage that little to no sample preparation is needed before the analysis, which reduces the amount of potential artifacts present in data acquisition and allows a more representative analysis of the sample to be acquired. For in-situ SCMS, the single-probe tip can be directly inserted into live eukaryotic cells such as HeLa cells, due to the small sampling tip size (&lt; 10 &#181;m), and this technique is capable of detecting a wide range of metabolites inside individual cells at near real-time. SCMS enables a greater sensitivity and accuracy of chemical information to be acquired at the single cell level, which could improve our understanding of biological processes at a more fundamental level than previously possible. The single-probe device can be potentially coupled with a variety of mass spectrometers for broad ranges of MSI and SCMS studies.

Here, we present protocols to perform both ambient mass spectrometry imaging (MSI) of tissues and in-situ live single cell MS (SCMS) analysis using the single-probe, which is a miniaturized multifunctional device for MS analysis.

单探头的应用:根据环境条件质谱成像和单细胞分析

Mass spectrometry imaging (MSI) and in-situ single cell mass spectrometry (SCMS) analysis under ambient conditions are two emerging fields with great ...

生物学

Introduction to Mass Spectrometry

Source: Laboratory of Dr. Khuloud Al-Jamal - King&#39;s College London

Mass spectrometry is an analytical chemistry technique that enables the identification of unknown compounds within a sample, the quantification of known materials, the determination of the structure, and chemical properties of different molecules.
A mass spectrometer is composed of an ionization source, an analyzer,&#160;and a detector. The process involves the ionization of chemical compounds to generate ions. When using inductively coupled plasma (ICP), samples containing elements of interest are introduced into argon plasma as aerosol droplets. The plasma dries the aerosol, dissociates the molecules, and then removes an electron from the components to be detected by the mass spectrometer. Other ionization methods such as electrospray ionization (ESI) and matrix assisted laser desorption ionization (MALDI) are used to analyze biological samples. Following the ionization procedure, ions are separated in the mass spectrometer according to their mass-to-charge ratio (m/z), and the relative abundance of each ion type is measured. Finally, the detector commonly consists in an electron multiplier where the collision of ions with a charged anode leads to a cascade of increasing number of electrons, which can be detected by an electrical circuit connected to a computer.
In this video, the procedure of ICP-MS analysis will be described by the detection of 56Fe as an example.

耦合扫描流动性测定仪和电感耦合等离子体质谱仪（SMPS-ICPMS）的实用指南

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挥发和氧化敏感的化合物使用冷进气系统和电子轰击质谱分析

用两个稳定 Isotopically 标记鞘磷脂种鞘磷脂的定量和定性方法

Versatile Dual-Inlet Sample Introduction System for Multi-Mode Single Particle Inductively Coupled Plasma Mass Spectrometry Analysis and Validation

使用循环离子淌度光谱仪进行串联离子淌度实验

通过液相色谱-捕获离子迁移谱-飞行时间质谱法检测食品基质中受管制的麦角生物碱

通过液相色谱-捕获离子迁移谱-飞行时间质谱法检测食品基质中受管制的麦角生物碱

通过液相色谱-捕获离子迁移谱-飞行时间质谱法检测食品基质中受管制的麦角生物碱

在脑组织成像金属激光剥蚀 - 电感耦合等离子体 - 质谱法（LA-ICP-MS）

单探头的应用:根据环境条件质谱成像和单细胞分析

质谱分析法导论