Welcome to the Biotage Peptide Synthesis Blogs.

      How to choose an ion pairing agent to improve your peptide purification

      Jul 22, 2019 4:28:04 PM / by Elizabeth Denton posted in Chromatography Fundamentals, Peptides, Reversed-phase, Solvents, Selekt, Isolera

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      Ion pairing agents are used in a variety of strategies to improve overall purification efficiency. In a previous post, I utilized ion pairing agents to increase the peptide’s hydrophobicity, improving retention by the stationary phase and enabling purification.  But what other strategies can be improved by using ion pairing agents?

      In this post, I’ll utilize ion pairing agents to enable rapid peptide purification by flash chromatography.  The use of ion pairing agents can in fact alter the peptide’s apparent hydrophobicity sufficiently that the desired peptide and it’s closely eluting impurities can be resolved.  The question is, which one to choose?

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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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      How does methanol as a mobile phase solvent impact peptide purification by reversed-phase flash chromatography?

      Jul 18, 2019 2:10:15 PM / by Elizabeth Denton posted in Chromatography Fundamentals, Peptides, Reversed-phase, Solvents, Green, Sfär

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      Recently there has been substantial motivation to consider and evaluate alternative, more environmentally friendly solvents.  Some countries have even gone so far as to ban some of the more toxic, yet commonly used solvents.  In addition to general toxicity, additional consideration in the green chemistry movement is the volume of solvent used in any particular application.  In this regard, purification solvent selection is closely monitored as they are often used in large quantities.

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      Does loading method influence my peptide recovery after purification?

      Jul 17, 2019 6:25:29 PM / by Elizabeth Denton posted in Chromatography Fundamentals, Peptides, Reversed-phase, Solvents, Workflow, Sfär, Loading Techniques, V-10, Isolera

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      In peptide purification, sample loading onto the column is rarely considered.  Most, if not all, HPLC instruments come equipped with a sample injection loop which demands a liquid injection of the sample for purification.  If you decide to use flash chromatography to purify your peptides though, liquid injection is no longer the exclusive method for sample introduction to the column.  Alternatively, dry loading crude material is a strategy often used in small molecule purification, particularly when sample solubility concerns arise.

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      Can I improve my peptide purification by increasing the column length?

      May 23, 2019 4:41:39 PM / by Elizabeth Denton posted in Chromatography Fundamentals, Peptides, Reversed-phase

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      There are several strategies often employed to improve peptide purity achieved using reversed phase HPLC.  These strategies can include, changing column length, particle size, particle functionality (C4 vs C18).  I have experimented a bit with some of these criteria while purifying peptides using reversed phase flash chromatography but one obvious change that I have not yet explored is the length of column.

      In today's post, I'll explore how the length of the cartridge affects the overall resolution and purification efficiency using reversed phase flash column chromatography.

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