Welcome to the Biotage Flash Purification Blogs.

    How does an alkaline pH affect normal-phase flash chromatography separations?

    April 7, 2020 at 6:25 PM / by Bob Bickler posted in pH, ionization


    The products of organic synthesis are designed with specific functional groups in order to possess desired properties. Depending on the compound’s functionality, it can be neutral, acidic, or basic as determined by a compound measurement called pKa or acid dissociation constant. Compounds with low pKa are typically acidic while those with high pKa tend to be basic. Compounds with a pKa near 7 are deemed neutral.

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    When should I use a pH modifier in flash column chromatography gradient?

    February 11, 2020 at 3:15 PM / by Bob Bickler posted in pH, acid, base


    Have you ever experienced compound tailing or streaking on your TLC plate or flash chromatography results and wondered what in the world is going on here? Well, there can be multiple reasons for this problem including poor mass-transfer kinetics, secondary solute-sorbent interactions, or unstable compound chemistry.

    In this post, I will discuss one technique that has been shown to work time and time again to address the issue.

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