Solvent System Selection
All but one article report on a single solvent system that was used for the featured separation. Six of the twelve solvent systems used were a mixture of four solvents. Four of the solvent systems used three solvents and two used five solvents. There was at least a dozen solvents used: hexane, light petroleum, ethyl acetate, dichloromethane, butanol, methytertbutylether, n-butanol, n-propanol, ethanol, methanol, acetonitrile, and water. This is a great testimony to the flexibility of CCC/CPC solvent usage. It is safe to say that the acetonitrile shortage has a minimum impact on CCC/CPC practitioners! Only two of the twelve solvent systems were modified with a solute. At least 82 solvent systems were tested to arrive at the twelve that were actually used for separation. The number is likely larger because two papers did not report in detail the solvent system selection process. The number of solvent systems that need to be tested is the flip side of the many possible solvent combinations that CCC/CPC users have available to them. Solvent system selection methods reflect the diversity of shake flask followed by UV, TLC, or HPLC. One of the publications used analytical CCC runs for solvent system selection.

Compounds Isolated
A total of 45 compounds were isolated with the help of CCC/CPC. This reflects a much needed movement away from the “one compound, one publication” CCC/CPC tradition. Interestingly, for only 27 of the 45 compounds was CCC/CPC reported as the final step of purification. This indicates that CCC/CPC is becoming an integrated part of larger isolation schemes rather than a “one step isolation of X from Y.” Again, this reflects a very encouraging trend. Only three of the 45 compounds isolated was described as “novel,” so there is still some work to be done in the area of using CCC/CPC to isolate new compounds.