Published On: May 31st, 2023Categories: Flash Chromatography, Silica GelComments Off on Are flash silica gels all the same?

This post highlights key chromatographic metrics—retention factor (k), selectivity (α), efficiency (N)—that collectively determine separation quality, as measured by resolution (Rₛ) Sorbent Technologies, Inc.+1.

In practical tests, three silica grades—Technical (40930), Standard (40930H), and Enhanced (40930M)—were compared using acetophenone mixtures on a 40g column at 30 mL/min Sorbent Technologies, Inc.+1.

  • Enhanced (40930M) delivered the best selectivity and resolution, though its efficiency was slightly lower due to lower water content.

  • Standard (40930H) offered better efficiency than Technical, striking a good balance of performance.

  • Technical (40930) performed poorest, with broader specifications compromising separation Sorbent Technologies, Inc.+1.

When testing higher sample loads (up to 5%), both Standard and Enhanced outperformed Technical. Baseline resolution became achievable with 40930H and 40930M, but not with 40930 Sorbent Technologies, Inc.+1.

Beyond those, two premium-grade silicas, 52500 and 52300, were evaluated. Both feature high purity and tight particle distribution, resulting in superior selectivity, resolution, and efficiency—outperforming the 40930 series Sorbent Technologies, Inc.+1.
Between the two, the smaller particles of 52300 provided dramatically sharper peaks and better efficiency, making it ideal when even with 5% loading, clear baseline separation is desired Sorbent Technologies, Inc.+1.


Key Takeaways:

  • 40930H is recommended over the basic grade for better overall performance.

  • 40930M excels when selectivity and low water content are critical.

  • 52500 and 52300 set a higher standard and are best for demanding separations, especially 52300 when tight efficiency is key.