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Silica is the most commonly used sorbent for flash column chromatography. When solvent is pumped through a column packed with dry silica you may notice it gets warm and sometimes down right hot!
Selectivity and solvent strength are the most important factors that determine success or failure of a chromatographic separation. These two independent dynamics apply to both normal- and reversed-pha...
For chemists, flash chromatography is part of their everyday synthesis workflow. For most syntheses, crude reaction mixtures are purified by normal-phase (aka adsorption) chromatography. There are tim...
Scaling up reversed-phase flash chromatography methods is often necessary as reaction scale increases. This is especially true when other non-chromatographic purification techniques do not work or mee...
As the popularity of prep-scale, reversed-phase flash chromatography increases, so does the frequency that I get asked this question, "How do I determine loading capacity in reversed-phase flash chrom...
How to choose between normal- and reversed-phase flash column chromatography is an excellent question and one that my readers often ask. Those who use column chromatography know that as long as the re...
With reversed-phase flash column chromatography becoming increasingly popular for routine purification, understanding how to make the cartridges last (since they cost more) is important to know.
Evaporative Light-Scattering Detection, or ELSD for short, is a technology used with liquid chromatography to see UV-transparent (and UV-absorbing) compounds. In a previous post I talked about some ap...
A question I hear a lot from chemists is “how much can I load”. The answer is always “it depends on your separation quality”. At that point I begin asking about the TLC data and purification goals. Pu...
When it comes to the purification of polar, water-soluble compounds reversed-phase chromatography is the most commonly used approach. However, because of strong stationary phase – mobile phase repulsi...