INTRODUCTION CHROMATOGRAPHY Chromatography was originally developed in the year 1903 by the Russian botanist Michael Tswett in percolating a petroleum ether extract through a glass column packed with powered calcium carbonate for the separation of colored pigments. Elution means a chromatographic separation involves the placing of the sample into a liquid or solid stationary phase and passing a liquid or gaseous mobile phase through or over it. Whether the separation takes place on a planar surface or in a column according to these chromatographic techniques are classified. …show more content…
Most of the drugs are polar in nature and preferred phase is the Reverse phase chromatography or High performance liquid chromatography. To make faster instead of a solvent being allowed to drip through a column under gravity, it is forced through under high pressures of up to 400 atmospheres. This is the better separation for the separation of the components in a mixture. Hplc employs a very finely divided mobile phase and a liquid phase. Few thousands of pounds per square inch must be pressurised in order to obtain a satisfactory flow rate. Diffusion is the process by which the rate of distribution of drugs between stationary and mobile phase is controlled. A faster and effective separation can be achieved if the diffusion is minimized. When compared to classical column chromatography high performance liquid chromatography is so called because of its improved performance. Due to high-pressure pumping system and sensitive detectors have transferred liquid chromatography into high speed, accurate, efficient and highly resolved method of