Welcome to the Biotage Peptide Synthesis Blogs.

      Analyzing crude peptide samples by Mass Spectrometry: what are the options

      Jan 10, 2020 3:30:02 PM / by Elizabeth Denton posted in Peptides, Troubleshooting and Optimization, HPLC

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      There are many techniques available to analyze and identify synthetic compounds that we are taught in the first few years of our chemistry education. While tools like NMR spectroscopy, IR spectroscopy, and others, are extremely useful for determining or confirming the structure of synthetic small molecules, these strategies are not as well suited for quick characterization of peptides. As a result, peptide chemists rely heavily on peak shape observed during a liquid chromatography step and mass spectrometry for mass confirmation.

      In today's post, I'll discuss several of the mass spectrometry techniques that are used for analyzing crude or purified peptide samples.

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      How does media pore size impact peptide resolution?

      Sep 27, 2019 3:19:01 PM / by Elizabeth Denton posted in Chromatography Fundamentals, Peptides, Reversed-phase, Green, Sfär, Media and Resin, Cost, V-10, HPLC

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      Purification by reversed-phase chromatography relies primarily on a hydrophobic interaction of the molecule with the alkyl chains bonded to the stationary phase for column retention and elution through a partitioning mechanism.  While this is certainly true for purification of peptides, surface area accessibility and media particle size also play critical roles in the resolving power of a particular stationary phase.  The particle size influences the loading capacity, however pore size greatly influences molecular accessibility and therefore resolving power.

      In today’s post, I will demonstrate how pore size can impact your peptide purification using flash column chromatography.

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      How to use a scouting column for your peptide purification

      Sep 27, 2019 3:13:39 PM / by Elizabeth Denton posted in Chromatography Fundamentals, Peptides, Reversed-phase, HPLC

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      In the past, when I have synthesized a new peptide, I always ran a “scout run” – a small scale injection, usually with an analytical HPLC column – to both get an idea of the crude purity and also to identify a shorter, more optimal gradient for the actual purification.  This strategy is still recommended when you want to use reversed phase flash chromatography for your purification strategy, but is there a better way?

      In today’s post, I’ll discuss using a scouting column to screen gradient conditions prior to peptide purification with reversed phase flash chromatography.

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      Peptide purification with flash column chromatography - a beginner's experience

      Jul 18, 2019 8:59:34 PM / by Elizabeth Denton posted in Peptides, Reversed-phase, Sfär, HPLC

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      As a peptide chemist, I was trained to purify my peptides with reversed-phase HPLC, just as many a peptide chemist before me. Despite the hundreds of hours I’ve logged in front of an HPLC, injecting samples and collecting peak fractions, I can’t imagine using any other method to purify my freshly synthesized and cleaved peptides.  In fact, you’d be hard pressed to convince me to try something else.  But here I am, trying something new.  Wish me luck!

      In this post, I’ll describe my experiences using flash chromatography to purify a new peptide sample.

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