相关实验视频
Updated: Aug 2, 2026

04:21
Small Volume 1-3L Filtration of Coastal Seawater Samples
Published on: June 19, 2009
11.2K
储存温度和过方法对沿海水样本中溶解微量金属度的影响
Anna Przibilla1,2, Susanna Iwainski1,3, Tristan Zimmermann1
1Institute of Coastal Environmental Chemistry/Department Inorganic Environmental Chemistry, Helmholtz-Zentrum Hereon, Geesthacht, Germany.
概括
过方法和储存方法对沿海水域中溶解微量元素的测量有重大影响. 适当的程序空白和仔细的样本存储对于准确的海洋学和生物地化学研究至关重要.
科学领域:
- 环境科学 环境科学
- 海洋学 海洋学 海洋学
- 分析化学 分析化学
背景情况:
- 微量元素对于海洋生物地球化学循环和海洋学过程至关重要.
- 精确测量溶解的微量元素需要仔细的样品准备,因为过和储存可以引入偏差.
研究的目的:
- 为了比较两种过方法 (压力与真空) 的准确性和可靠性,用于沿海和河口水样.
- 评估短期 (长达9周) 冷和冷藏对溶解微量元素度的影响.
- 为了评估过空白在微量元素分析中的重要性.
主要方法:
- 沿海水样品经过压力过 (NucleporeTM) 和真空过 (DigiFILTERTM).
- 在使用 seaFAST-ICP-MS 的方法分析了 22 种溶解的微量元素 (Cd, Ce, Co, Cu, Dy, Er, Eu, Fe, Ho, La, Mn, Mo, Nd, Pb, Pr, Sm, Tb, U, V, W, Y, Zn) 的过物.
- 样品在-18°C或4°C下保存长达9周,以评估储存效应.
主要成果:
- DigiFILTERTM 显示了低过率的空白,适合在良好的可重复性下量化所有分析元素.
- 在Ce和Fe等元素的过方法之间观察到测量度的显著差异.
- 储存显著改变了度:冷样本中的损失为20%,冷样本中 (63%), (64%) 和 (93%) 的损失很大.
结论:
- 过方法和储存条件都对沿海水中的溶解微量元素度产生重大影响.
- 必须测量和报告程序空白,包括过空白,以使方法可比.
- 冷和冷储存带来了显著的偏差,需要快速分析或优化保存技术.
相关概念视频
Preparation of Samples for Electron Microscopy
To be visualized by an electron microscope, either transmission or scanning, biological samples need to be fixed (stabilized) so the electron beam does not destroy them and dried thoroughly (desiccated/dehydrated) so the vacuum does not affect them. Fixation needs to be done as quickly as possible because the sample properties will start changing as soon as it is removed from its natural environment. For example, in a tissue sample, the oxygen levels begin decreasing, causing an altered...
Colloidal precipitates
The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...
Washing, Drying, and Ignition of Precipitates
After filtration, the precipitate is washed to remove coprecipitated impurities and any remaining mother liquor. Colloidal precipitates, such as silver chloride, are washed with an electrolyte (such as dilute nitric acid) to prevent the peptization of the precipitate. In the case of slightly soluble precipitates, the wash solution contains a common ion to reduce solubility. Lead sulfate, which is slightly soluble in water, is washed with dilute sulfuric acid. Similarly, wash solutions may be...
Precipitation and Co-precipitation
Precipitation and coprecipitation methods can be used to separate a mixture of ions in a solution. In qualitative inorganic analysis, ions that form sparingly soluble precipitates with the same reagent are separated based on the differences in solubility products. For example, consider the separation of Cu(II) and Fe(II) ions by precipitation as insoluble sulfides. First, copper(II) sulfide is precipitated by the addition of acidic H2S, where the dissociation of H2S is suppressed. Adding H2S...
Extraction: Advanced Methods
Metal ions can be separated from one another by complexation with organic ligands–the chelating agent– to form uncharged chelates. Here, the chelating agent must contain hydrophobic groups and behave as a weak acid, losing a proton to bind with the metal. Since most organic ligands used in this process are insoluble or undergo oxidation in the aqueous phase, the chelating agent is initially added to the organic phase and extracted into the aqueous phase. The metal-ligand complex is formed in...
Sample Preparation for Analysis: Advanced Techniques
Accurate analysis of complex samples often requires advanced preparation techniques to achieve reliable and reproducible results. Samples containing inorganic or organic materials can be challenging to dissolve or decompose effectively. Standard sample preparation methods include acid digestion, fusion, dry ashing, and wet digestion.
Acid digestion with strong acids is commonly used to dissolve inorganic materials that are insoluble (do not dissolve) in water. This method can be useful for...
Acid digestion with strong acids is commonly used to dissolve inorganic materials that are insoluble (do not dissolve) in water. This method can be useful for...

