Flash Chromatography method development has historically been done using TLC plates. While this technique works in normal phase (silica, aminefunctionalized silica), differences in media properties between the TLC and flash column in reversed phase can provide different selectivity and not provide accurate method information. For reversed phase chromatography, TLC is quite limited and not very useful due to poor water wettability. An alternative approach is provided by scaling columns.
Biotage Sfär columns are quality tested to ensure they meet stringent performance criteria including efficiency and peak symmetry. Each CE-marked column is built using inert, foodgrade plastics for lower extractables, cleaner fractions, and packed to provide excellent resolution.
Die Flash-Chromatographie ist die bevorzugte Reinigungsmethode für organische Stoffe, Arzneimittel und Naturstoffe. In jüngster Zeit hat sie auch die Peptidchemie erobert, verfügt sie doch über die Fähigkeit, eine Vielzahl unterschiedlicher Verbindungen effizienter zu trennen, als dies mit anderen Vorreinigungsverfahren wie z. B. dem Ausfällen (Protein-Crash) oder der Flüssig-Flüssig-Extraktion möglich ist. Zur Herstellung reiner Verbindungen können Chemiker je nach dem gewünschten Reinheitsgrad auf eine Vielzahl unterschiedlicher Variablen zurückgreifen. In diesem Whitepaper möchten wir die Faktoren erläutern, die für eine erfolgreiche Aufreinigung mithilfe der Flash-Chromatographie kontrolliert werden müssen.
Flash chromatography, a staple component of medicinal chemistry workflow, consumes a lot of organic solvent (upwards of half a million liters annually in just North America). Most, of this organic waste is incinerated off-site, liberating CO2 into the atmosphere. Because of this environmental impact, many companies are instituting requirements to reduce organic solvent waste but leaving the implementation to their chemistry departments. In this poster, we describe several proven ways to reduce solvent use without sacrificing purification efficiency.
Flash purification involves a simple liquid chromatography technique » Method development uses TLC as a way of deciding the parameters for the separation » Isocratic separations are easiest to develop, but gradient separations are more powerful » Software in the Isolera helps with conversion of an isocratic separation to a gradient » It is possible with the Spektra software to run step gradients » Loading options are dependent on the column type » SNAP offers the most flexibility » Care must be taken to choose the best loading option to get good purifications
Flash Chromatography is the primary tool used by medicinal chemists for reaction mixture purification. Over the past 10 or so years, the use of reversed-phase flash chromatography for reaction mixture purification has increased dramatically due to both chromatographic and non-chromatographic reasons.
Normal-phase flash chromatography1 has been widely adopted as the method of choice for separation of product mixtures and reaction by-products. One of the most significant developments in this area concerns the practical separation of polar molecules. Reversed-phase purification is a modification of normalphase chromatography that provides an efficient mechanism for the separation of polar compounds.
Thin-layer chromatography (TLC) is a commonly used method development tool for flash purification. Product mixtures separated using TLC generally can be purified by flash chromatography using the identical solvent system. The method transfer accuracy of TLC to flash is based on the TLC silica and flash silica properties. When identical, the equation 1/Rf = CV holds, where Rf is the retention factor of a compound separated by TLC, and CV is the number of column volumes required to elute a compound. Cartridge loading capacity is based on the difference in CV (DCV) between two adjacent compounds.
To save money on consumables, many chemists choose to reuse silica flash cartridges. This is true but risks purification results because chromatographic separation performance will change from run to run which reduces purification quality, especially in normal phase systems. Regardless of the cartridge brand used, repeated use of silica flash cartridges results in loss of compound resolution and therefore fraction purity.