In layman’s terms, Chromatography refers to the movement of vapors or droplets when a mixture is passed through a medium. Of course, most of us are not Chemistry majors, so here is a simplified definition of the topic: chromatography is simply a laboratory experiment that helps people see the separation of a mixture’s different components.
Suppose the mixture in question contains more than a few unknown substances. In that case, scientists can use chromatography to separate the individual substances, and in doing so, they can learn what these substances are.
What is chromatography, many people have wondered? Historically, chromatography had been popular among artists and textile merchants who wanted to mass-produce industrial color dyes. The separation and identification of ingredients gave them an edge in textile dyes’ mass production and brought in a hefty sum.
Though this practice is still used periodically in art, it has become much more popular amongst scientists who use it in a much more educational manner.
How it works
The mixture is dissolved into a mobile phase by singing this technique and then transferred through a stationary phase. The droplets/molecules begin to separate from the mixture at the stationary phase as they individually react with the medium. As these droplets start to unravel, each can be individually identified through their color, speed, and consistency.
It works because of differences in the properties of molecules in the materials. Molecules like, for example, water, have polarity, making them act like magnets. Some molecules are ionic, meaning that the atoms are held together by their charge differences.
There are three main types of scientific procedure. It is to be noted that chromatography has now developed different variations of itself. Each of these variations is better suited to separate a mixture of the elements. So that scientists can use these variations for other substances and find more accurate results.
The following are the three main types:
1. Gas Chromatography
This experiment is when a mixture is vaporized and carried through a stationary phase with usually the gas helium or nitrogen as they are completely inert. This mixture’s separated contents are then identified as they reach through the column and onto the detector. Some components take longer than others.
- Fair resolution as sharp and symmetric peaks show it.
- Higher chances of reproducibility and repeatability of retention times
- Higher precisions and accuracy.
- Relatively inexpensive and modular.
- It can be used with minimal amounts of sample.
- Unsuitable for labile samples.
- Samples need to be soluble and not react to the column.
- Hard or impossible to recover separated components.
2. Thin Layer Chromatography
This kind of chromatography or TLC conducts the separation on a thin layer of absorbent material, typically coating a silica gel on a glass plate or plastic sheet.
- It is legally an easy method of separation of the components.
- Fewer types of equipment are used in this technique.
- The process takes less time than others.
- All components of the UV are achievable.
- The components of complex mixtures are easier to separate.
- The results are difficult to reproduce.
- Applicable only for soluble mixtures making it less diverse.
- It is not an automated process.
- The separation process is limited to a particular time.
- The analysis is qualitative, not quantitative.
3. Paper chromatography
In paper chromatography, substances are distributed between a stationary phase and a mobile phase. In analytical chemistry, it is a technique of separation of dissolved chemical substances. It is an inexpensive but powerful analytical tool that requires minimal quantities.
- Requires very little quantitative material
- Paper chromatography is also relatively cheaper than other options.
- Both unknown organic and inorganic materials can be used in this method.
- Larger quantities of samples cannot be processed in this option.
- Complex mixtures and materials cannot be separated using this process.
- Less accurate compared to some other varieties of chromatography.
As reviewed, this article aids in mentioning the few best ways of conducting accurate and efficient chromatography. The analysis is used to calculate and separate molecules and materials in chemical products. Scientists use these methods to analyze and examine organic and inorganic materials.
Chromatography is such an important and useful technique that two Nobel prizes have been awarded to chromatograph specialists. This can be used in many different ways. Some people use it to tell differences between solids and liquids, while others use it to determine what substances have to be used. It is a beneficial scientific procedure.