what is hplc

Column chromatography solvent selection

The convenience and versatility of column chromatography have made it one of the most commonly used separation techniques for compounds. Column chromatography is also able to separate a number of analytes from a sample mixture. One more advantage of column chromatography is that using this purification technique does not require much information about the physical properties of the compound, making this method extremely valuable when separating novel compounds.If the chemical characteristics of your sample mixture are more complex, then there are some options that are available to separate pure analytes.

The travel rate of a compound through the column extremely depends on the use of the mobile phase. Typically, the more polar solvent can make the compound travel quickly through the column. For the solid phase, polar solvents include better affinity, permit the compounds to elute more quickly. Care should be taken to confirm that the solvent system selected for column chromatography has the suitable polarity to make separation among the compounds in the sample mixture. Solvent or mobile phase selection is significant for separated by column chromatography.

To recognize a better solvent system for column chromatography, a sequence of thin-layer chromatography (TLC) trials must be performed prior to conducting experiments. In order to use a binary solvent system, it may be necessary in some cases. The solvent or mobile system used relies on the behavior of the sample component on the silica gel. Generally, we select a solvent or mobile system in which the compound we wish to separate has an Rf value of about 0.3, although, many analysts run gradient systems. It starts with hexane, and then gradually increases the solvent polarity until the compound is eluted. It is also the method of HPLC.


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