History of chromatography facts for kids
Chromatography is a clever science method used to separate different parts of a mixture. Imagine you have a mix of colors, like in a marker. Chromatography can pull those colors apart so you can see each one individually! The word "chromatography" actually means "color writing." This technique was first used in the early 1900s to separate plant colors, like the green in chlorophyll or the orange and yellow in carotenoids. Over time, new types of chromatography were invented, making it super useful for many different separation and analysis jobs, especially in studying living things and chemicals.
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Early Ideas for Separation
The very first ideas that led to chromatography came from scientists in the mid-1800s. One German chemist, Friedlieb Ferdinand Runge, described in 1855 how he used paper to look at different dyes. He would drop chemicals onto special filter paper, and they would create unique color patterns. However, experts today say his work was more like a "spot test" than true chromatography.
In the 1860s, Christian Friedrich Schönbein and his student Friedrich Goppelsroeder studied how different substances moved through filter paper at different speeds. Schönbein called this "capillary analysis." He thought tiny tubes in the paper (capillary action) were responsible for the movement. Goppelsroeder spent much of his career using this method. Unlike modern paper chromatography, their method created overlapping areas of chemicals, not separate bands.
Later, in 1927, Raphael E. Liesegang improved these methods. He put filter strips in closed containers with special liquids. By 1943, he was using small spots of samples on filter paper, dipping them into a pure liquid to separate them. This was very similar to how modern paper chromatography works.
Around the same time, in 1897, an American chemist named David Talbot Day noticed something interesting. Crude oil would separate into colored bands as it moved up through clay or limestone. He shared his discovery in Paris in 1900, and it caused a stir!
Tsvet and Column Chromatography
The invention of true chromatography is usually given to a Russian-Italian botanist named Mikhail Tsvet. He used his observations with filter paper to create a new way to separate things. He used a column filled with calcium carbonate (a white powder) to separate yellow, orange, and green colors from plants. These colors are now known as xanthophylls, carotenes, and chlorophylls.
Tsvet first described his method in 1901 in Saint Petersburg. He first used the word chromatography in print in 1906 in a German science journal. His last name, "Tsvet," actually means "color" in Russian. Some people think he chose the name "color writing" (chromatography) to make sure his name would be remembered.
In 1903, Tsvet also described using filter paper to study plant colors. He found that some colors, like orange carotenes, could be pulled out of leaves with certain liquids. But others, like chlorophyll, needed stronger liquids. He realized that chlorophyll was "stuck" to the plant tissue. To test this, he put dissolved colors on filter paper. He then used different liquids to see which could pull the colors off the paper. He found the same pattern as with leaves: carotene came off easily, but chlorophyll needed stronger liquids.
Tsvet's amazing work was not widely used until the 1930s.
Martin and Synge and New Separations
Chromatography methods didn't change much after Tsvet's work until the mid-1900s. Then, Archer John Porter Martin and Richard Laurence Millington Synge made huge breakthroughs. They combined chromatography with another technique called "solvent extraction." This allowed them to separate chemicals that were very similar.
Martin and Synge started working together in 1938. Martin was good at designing equipment, and Synge was trying to separate amino acids (the building blocks of proteins). After trying different methods, Martin had an idea: use a special gel called silica gel in columns to hold water still while another liquid flowed through. They showed how well this worked by separating amino acids.
Starting in 1941, they published many papers describing their powerful new ways to separate amino acids and other chemicals. They also looked for easier ways to identify amino acids. In 1943 and 1944, they described using filter paper as a stationary phase to separate amino acids. This became known as paper chromatography. By 1947, Martin, Synge, and their team used this method to figure out the sequence of a small protein called Gramicidin S. These paper chromatography methods were also key to Fred Sanger figuring out the amino acid sequence of insulin.
Improving the Techniques
Martin, working with Anthony T. James, went on to develop gas chromatography (GC) starting in 1949. They had actually predicted how GC would work in their 1941 paper! In 1952, when Martin received the Nobel Prize in Chemistry (which he shared with Synge), he announced that gas chromatography could successfully separate many natural compounds. Before this, Erika Cremer had laid the groundwork for GC in 1944. Her student, Fritz Prior, built the first gas chromatograph in 1947, separating oxygen and carbon dioxide.
Gas chromatography was easy and efficient for separating organic chemicals. This led to its quick adoption and the fast development of new ways to "see" the separated chemicals. The thermal conductivity detector was described in 1954. Then came the flame ionization detector in 1958, and James Lovelock introduced the electron capture detector that same year. Scientists also started combining mass spectrometers with gas chromatography in the late 1950s.
The work of Martin and Synge also paved the way for high performance liquid chromatography (HPLC). They suggested that using tiny particles and pressure could make liquid chromatography much faster. This became widely practical by the late 1960s.
Thin Layer Chromatography
The first steps in thin layer chromatography happened in the 1940s. This technique quickly improved in the 1950s. Scientists started using larger plates and more stable materials for the thin layers that do the separating.
Later Discoveries
In 1987, Pedro Cuatrecasas and Meir Wilchek won the Wolf Prize in Medicine. They were recognized for inventing and developing affinity chromatography. This special type of chromatography has many important uses in medical science.
See also
In Spanish: Historia de la cromatografía para niños
