The FLASH purification column is the heart of the FLASH purification system, just like the engine in a car. To do well, you must first sharpen your tools. Choosing the correct FLASH purification column is the most critical part of the entire purification. Today we will talk about the connotation of purification column-stationary phase.
The stationary phase is also commonly known as the filler, which is the core part of the chromatography. To determine the stationary phase packed in the FLASH purification column, three aspects of the stationary phase information must be determined in sequence: matrix type, surface modification/bonding phase, and matrix parameters. Hawach now introduces the type of matrix FLASH purification column stationary phase.
Matrix
The matrix isthe basic material composed of the stationary phase, and the commonly used matrix materials are divided into three categories: inorganic materials, organic materials and composite materials. Inorganic materials include silica gel, alumina, etc.; organic materials are mainly polymer materials such as gels; composite materials usually refer to composite materials that combine inorganic and organic materials through hybridization, coating, and coating.
Silica gel is the most widely used matrix in FLASH purification. Silica gel for chromatography has a porous structure, high mechanical strength and thermal stability, excellent pore structure and specific surface area, and its surface contains a large number of active hydroxyl groups. It is used in normal phase purification systems. It plays a very important role in the separation and purification of compounds. Hawach also have standard Silica gel flash column.
At the same time, the surface of silica gel is easily modified to form other bonded stationary phases. There are many kinds of stationary phases modified with silica gel matrix, and the separation and purification effect is much better than other matrixes. However, the stability of silica gel matrix under alkaline conditions is relatively poor.
At the same time, the presence of its hydroxyl group can easily cause irreversible adsorption of some substances, especially alkaline substances. In addition, when applied to the separation and purification of some biomolecule samples, the sample will have non-specific adsorption. Or denature the sample, resulting in poorer peak shape of sample elution in the chromatogram and lower sample recovery rate.
The alumina matrix has high mechanical strength, good chemical stability, unique selectivity to some compounds, and good complementarity to the silica matrix. However, it is difficult to modify the surface of alumina, so it is still used in normal phase purification systems at most and a small amount in ion exchange systems.
The organic matrix is mostly polymer gel material (such as resin, polystyrene divinyl copolymer, etc.), which has better chemical stability than silica gel (applicable pH value can range from 1 to 12). The sample basically does not undergo denaturation reaction, nor is it prone to irreversible adsorption.
After modification, it has a wide range of applications in the separation and purification of biomolecules such as proteins and carbohydrates in ion exchange chromatography, size exclusion chromatography and reversed-phase hydrophobic chromatography. However, compared with inorganic substrates such as silica gel, the separation mechanical strength that the organic matrix stationary phase can withstand is lower, and the separation and purification effect is poor, which limits its scope of application in purification.
The composite matrix is compatible and neutralizes the advantages and disadvantages of the inorganic matrix and the organic matrix. However, the corresponding stationary phases of the composite matrix are generally expensive, so they are less used in preparation and purification.
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