Welcome to the Biotage Flash Purification Blogs.

      What are good reversed-phase dry load options?

      July 23, 2019 at 2:40 PM / by Bob Bickler posted in dry load, reversed-phase, sfär

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      Using a “dry” loading technique with flash chromatography typically improves compound purity and overall separation quality compared to liquid loading. The reasons for this I have prophesized previously and include:

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      Setting the Right Flow Rate for Flash Column Chromatography

      July 10, 2019 at 3:16 PM / by Bob Bickler posted in Developments

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      How does flow rate impact my flash column chromatography separation?  This is the kind of question I frequently get.  After all, we all know that flow rates that are too high or too low can result in bad prep HPLC chromatography.  Well, this is not necessarily true in flash chromatography.

      In chromatography there are three inter-related variables which impact your separation and are represented on the  chromatographer’s triangle.

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      Which loading method should I use for purification by flash chromatography?

      July 10, 2019 at 3:14 PM / by Bob Bickler posted in Developments

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      Getting the most benefit from your crude sample purification with column chromatography or flash chromatography involves optimizing many variables.  In previous posts I have talked about selecting the best solvents, their ratios, and maximizing load based on TLC Rf data. These are all important chromatography-generated variables but now I would like to share some tips on actual technique differences and their impact on purification performance.

      In particular in this post I will focus on the benefits and drawbacks of liquid loading and dry loading.  Both have their place in liquid chromatography but when should one technique be used over another?

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      How do I determine loading capacity in reverse phase flash column chromatography?

      July 10, 2019 at 3:01 PM / by Bob Bickler posted in Developments, Flash Theory

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      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 chromatography?"

      In the world of HPLC, loading capacity isn’t normally a concern as it is primarily an analytical technique.  In the synthetic organic chemistry world, most purification is performed with silica gel where flash column purification methods are developed and loading capacity estimated from TLC data.  However, when normal-phase flash does not work and reversed-phase flash is needed, the question of how to determine reversed-phase loading capacity comes up.

      In this post I will attempt to provide some guidelines to help you understand and determine reversed-phase flash chromatography loading capacity.

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      How do I develop a reversed-phase flash column chromatography method?

      July 10, 2019 at 2:53 PM / by Bob Bickler posted in Developments

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      Method transfer from reversed-phase TLC (thin layer chromatography) to reversed-phase flash column chromatography can be very challenging.  Because of this, I often recommend using HPLC for reversed-phase flash chromatography method development. This really is a straight-forward process if you start with the right HPLC column and know a little about your HPLC system's detector.

      In this post, I will share some tips on how to develop a reversed-phase flash purification method using HPLC.

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      How to minimize particulate build-up in flash chromatography systems

      July 9, 2019 at 3:23 PM / by Bob Bickler posted in blockage, pressure, particulate

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      In order to perform flash chromatography consistently, the equipment you use must be properly maintained by following some “best practices”. These best practices include using clean solvents (I typically use ACS grade), volatile organic modifiers, and quality columns.

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