For many chemists lab budgets, especially for consumable items, are limited. One way of trying to stretch their lab budget is to reuse disposable flash chromatography cartridges.
In this post I will show how regardless of the cartridge brand used, repeated use of silica flash cartridges results in loss of compound resolution and fraction purity.
To save money on consumables, many chemists choose to reuse silica flash cartridges. This risks purification results because chromatographic separation performance will change from run to run, which reduces purification quality, especially in normal phase flash systems.
Claims are often made that cartridges can be reused. This is true if the separations are relatively simple. Though reusing a silica flash cartridge may reduce the overall cost per purification, the quality of those second and later purifications will not be as good as the first thereby reducing separation efficiency and fraction purity.
To prove this point a solution of five compounds was purified on two flash cartridge brands, one from Biotage and another from another well known flash cartridge producer. The method used was a simple 5% to 40% ethyl acetate in hexane gradient.
The results show that within three runs separations are degraded in both cartridges although the higher surface area Biotage® SNAP Ultra silica cartridge (Figure 1) appears to degrade less than the competitive spherical silica (Figure 2) over the same elapsed time.
So, if your product purity is important, I suggest using a new silica column for every reaction mixture purification.
For more helpful flash chromatography information, download our white paper - Successful Flash Chromatography.