1. Chromatography The chromatography is discovered by a botanist called Tswett in 1906 when he tried to separate the constituents of a herbal extract by using a column containing gel material. He observed bands of colour separated on the gel material and the colour separation was called chromatography.

2. Column chromatography

3. Column chromatography
This method of separation is called gel, molecular sieve or size-exclusion mechanism of separation.
Size exclusion

4. Thin layer chromatography (TLC)

5. Thin layer chromatography (TLC)

6. Thin layer chromatography (TLC)
Vertical ascending

7. Thin layer chromatography (TLC)
Vertical descending

8. Thin layer chromatography (TLC)
Horizontal

9. Thin layer chromatography (TLC)
The polar drugs are adsorbed temporarily on the polar stationary phase surface. The most common stationary phase used for this purpose is silica. Silica has a chemical composition similar to glass SiO2. xH2O
Silicic acid
Silica

10. Thin layer chromatography (TLC)
Adsorption
Partioning

11. Gas chromatography (GC)

12. Gas chromatography (GC)
The carrier is a gas such as nitrogen or helium. The column is long to retain the analyte longer and it is filled with polydimethylsiloxane particles or relevant derivatives.

13. Gas chromatography (GC)

14. Gas chromatography (GC)
FID (flame ionisation detector)

15. Gas chromatography (GC)
ECD (electron capture detector)
This detector has a radioactive element. The radioactive element can produce a rich field of electrons. Once the compounds contain electronegative elements such as halogens reach the electron field they will capture some of the electrons and this change in the electrical field will give a response proportion with the concentration of the halogenated analytes. This detector is widely used in the analysis of halocompounds such as pesticides and herbicides