What is Chromatography?

If you work in the chemical industry, you must have heard about the technique of chromatography. Despite being a common procedure, many people still aren’t familiar with什么是色谱以及如何确切工作。如果您对这个主题感到困惑，那么您来了。本文包括有关色谱法的所有详细信息。让我们开始从色谱法的含义和定义开始。

色谱的含义

根据字典定义，色谱法是一种通过利用不同分子的不同特性来分离溶液（气或液体）成分的方法。该技术采用流动相（气体或液体）来运输通过固定相（固体或液体）分析的溶液，该溶液吸收或阻碍了溶液的不同分量到不同程度，从而导致它们作为不同层的分离。它是分析科学家手中的宝贵工具，用于分离和定量有机化合物混合物中的组件。

History and Basics of Chromatography

该技术起源于Mikhail Tswett的开创性作品，他在1900年使用包装的玻璃柱将植物色素分离出来。由于分离的颜料的颜色不同，并分离为不同的带，因此将技术作为色谱法创造为含义分离。

Over the years chromatography has evolved and advanced into versions such as HPLC,GC, HPTLC and SFC all of which to this day are based on the separation of mixture components through selective physico-chemical interactions and partitioning between the stationary and mobile phases.

为什么我们使用色谱法？

Since its evolution chromatography has found wide use in separation of components of mixtures ranging from simplest gases to most complex hydrocarbon mixtures containing hundreds of different compounds. Samples can be gaseous, liquids or even solids which are readily soluble in suitable solvents.

Due to its versatility the applications cover complete range of chemical compounds having diverse characteristics such as boiling range, molecular weights, volatilities, and thermal stabilities. Gas chromatography, Liquid chromatography,Thin-layer chromatography，超级关键的流体色谱和连字符技术（例如GC - MS和LC - MS）涵盖了各种领域的大量应用，例如药品，材料开发，食品，石油产品以及法医研究，需要非常高的分辨率和检测限制。

A few application of chromatography in different industries are:

化学工业

• 污染物在农药和油中的检测
• Water sample testing
• Air quality checks
• Numerous applications in life sciences

制药行业

• Taking element composition and its molecular weight to separate compounds
• During the process of drug development
• Detecting chemicals or trace elements in various samples with proper analysis
• Examination of mixture purity
• Identification of unknown compounds

Forensic Industry

• 犯罪现场测试中的血液和头发样本分析
• Forensic pathology

Food Industry

• Identifying the food products’ nutritional values and quality
• 发现添加剂和食物变质

分子生物学研究

• The fuel industry, biochemical processes, and biotechnology use HPLC for purification and fractionation process
• Metabolomics and proteomics study through specific chromatography techniques
• Nucleic acid research with specificchromatography methods

These are only the popular applications of chromatography. The technique is used in various other places and industries.

色谱的基本工作

色谱法的确切过程将取决于您要使用的位置以及选择哪种方法（这些方法将在文章稍后探索）。但是，我们仍然可以定义一个由简单的四个步骤组成的基本过程：

• Step 1: Careful exposure of a specific analyte amount to the mobile phase stream that was already running.
• Step 2: Then, the analyte is carried out through the stationary phase with the help of the mobile phase.
• Step 3: Finally, the separation takes place when the analyte components react with the stationary phase at different levels. Some of them react more, while others don’t.
• Step 4: The separated out analyte components are then again carried out by the mobile phase. It then takes the components to a separate instrument. There, they get quantified with the proper detection of their presence.

And in these four steps, the process gets complete. We can say that chromatography is divided into three basic components: Mobile Phase, Stationary Phase, and Separated Molecules.

Let’s now get into the details of the use of different parts of chromatography.

Chromatography Parts

The four steps aren’t enough to understand how chromatography works. You also need to know about the different elements of the process, along with their working. Only then will you be able to learn the concept.

Chromatography Columns

Separation of sample components before detection is the essence of chromatographic techniques. A chromatographic system uses a column to achieve the desired separation. A column comprises of a tube packed with a stationary phase on which separation takes place based on physico – chemical interactions of separating compounds with the stationary phase. The mobile phase or the carrier gas elutes less weakly retained components first followed by more strongly retained components.The column dimensions and composition is based on the chromatographic technique selected and the degree of required separation. In generalHPLC列比GC列更短且更宽.

Chromatographic Detectors

分离后，各个组件到达检测器，该检测器根据洗脱化合物的量，根据面积或峰值高度提供响应。每种色谱分离技术都根据洗脱化合物的性质提供一系列探测器。

可以具体的特定compoun检测d or a range of compounds or it can depend on some physical properties such as reflective index of the mobile phase. Such detectors are referred to as bulk property detectors in comparison to selective or specific detectors.

Chromatographic Data

Chromatographic separations appear as peaks in the chromatogram except for thin-layer chromatography for which separate zones are seen on the plate. Chromatographic peaks are separated in time in the chromatogram depending on the nature of separating compounds and the separation efficiency of the column. Sharp well resolved peaks indicate high degree of column resolution whereas broad or overlapping peaks are indicative of poor resolution.

Each peak represents a sample component and is characterized by its retention time under defined operating conditions. For purposes of quantification the peak height or more accurately the area under the peak defines the amount of the component present in the mixture.

定量方法需要在混合物中特定成分的百分比组成，并根据以下假定进行此类估计，即检测器对所有分量均等响应，并为每种化合物产生峰值。

%of analyte = \(\frac{Area of analyte peak}{sum total area of all peaks}\)X100

Quite often the amount of analyte is specified in relation to another compound which is referred to as a reference standard having established traceability. Such compounds should be available in pure form and have chemical identity which is same or close to the identity of the analyte to be determined.

Modern-day analytical systems come equipped with sophisticated application softwares which are capable of operational control, data interpolation and calculations to achieve the desired results.

Common Chromatography Methods

基于元素的分离基础进行的一些一般色谱方法是：

• 色谱柱色谱法
• Affinity Chromatography
• 薄层色谱法
• 离子交换色谱
• manbetx官方
• 高压液相色谱（HPLC)
• 纸色谱法
• Gel-Permeation Chromatography (Molecular Sieve)
• Dye-Ligand Chromatography
• Pseudo-Affinity Chromatography
• Hydrophobic Interaction Chromatography

现在，您有了“什么是色谱？”的基本问题的答案，您将渴望更多地了解色谱技术。简单地注册到我们的免费课程和主菜单上列出的课程中列出的高级证书程序。