Instructions for Using the Column
Liquid chromatography is a type of separation and analysis technique characterized by a liquid as the mobile phase. The stationary phase can take many forms, such as paper, sheets, and packed beds. In the development of chromatographic techniques, in order to distinguish between various methods, their respective nomenclatures are generated according to the form of the stationary phase, such as paper chromatography, thin layer chromatography and column liquid chromatography.
Instructions for using the column:
1. Precautions before using the column:
The column storage solution is not specified, and is the mobile phase shown in the evaluation report. Before use, be sure to check if the column storage solution is miscible with the mobile phase of the sample to be analyzed. In reversed-phase chromatography, if a high concentration of salt or buffer is used as the eluent, a low concentration of organic phase eluent of about 10% should be used first, otherwise the salt in the buffer is at a high concentration of organic phase. It is easy to precipitate and block the column.
2. Mobile phase:
The various organic solvents used in the mobile phase should be chromatographed as much as possible, and the water with the mobile phase is preferably ultra-pure water or double-distilled water of all glassware. It is even better if the prepared mobile phase is filtered once more through a 0.45 μm filter, especially a salt-containing mobile phase. In addition, devices such as containers for mobile phases and in-line filters in chromatography systems should be cleaned or replaced periodically.
Conventional silica-based bonded phase fillers typically have a pH range of 2.0-8.0. BDS C18 is suitable for basic compounds with a pH range of 2.0-10.0. When it is necessary to use the column under the boundary conditions of the pH range, immediately after each use, clean it with a solvent suitable for column storage and compatible with the flow used, and completely replace the original flow phase.
The sample should also be as clean as possible. The sample filter or sample pretreatment column (SPE) can be used to pretreat the sample; if the sample is inconvenient to handle, use a guard column. When analyzing samples by normal phase chromatography, all solvents and samples should be strictly dehydrated.