Chromatography has a history of over eighty years since its invention. It is a commonly used method for purifying and separating organic or inorganic substances. Chromatography in which the stationary phase is more polar than the mobile phase is called normal-phase chromatography, and vice versa, it is called reversed-phase chromatography. According to the principle of "like dissolves like," substances with higher solubility in the stationary phase in a mixture elute later, have longer retention times, and are more difficult to elute.