Installation Process and Precautions for Use and Maintenance of HPLC Columns
Installation Process, Precautions Use and Maintenance of HPLC Columns
Before installation the HPLC column, it is better to determine the carrier gas flow, only the carrier gas before heating the column will damage the equipment. After the installation of the HPLC column and the system leak collection work, it can be aged, raised to a certain constant temperature, but not beyond the upper limit of temperature.
After reaching the aging temperature, record and observe the baseline, the initial trend should continue to rise. When the HPLC column is connected to the injection port, the insertion depth of the chromatographic column in the injection port should be determined according to the specifications of the instrument used. Some need a long distance, some can be inserted correctly and properly to ensure the correctness of the experimental results to the greatest extent.
High purity nitrogen or hydrogen is preferred for carrier gas, which can prolong the life of the HPLC column and reduce background noise to a great extent. After the hot-selling HPLC chromatographic column is installed correctly, the mixture separation experiment can be started safely.
In the process of use, we should pay attention to whether there is any abnormal phenomenon in the chromatographic column, such as whether the image is normal or not, whether the performance of the HPLC column has decreased, and then we can deal with the corresponding problems with the right medicine.
Service Life of HPLC Column
Generally, the life of an HPLC column can be more than 2 years when used correctly. Fillers based on silica gel can only be used in the pH range of 2-9.
Chromatography is a separation and analysis method and the separation is the core. Therefore, HPLC columns are the heart of the chromatographic system. The requirements for the column are high efficiency, good selectivity and fast analysis speed. Generally, the column length of about 10~30cm can meet the needs of complex mixture analysis. To achieve the optimal efficiency of HPLC columns, it is necessary to have reasonable column structure and filling technology.
Column filling and performance evaluation
The filling technology is an important link for the acquisition of HPLC columns. But the fundamental problem lies in the performance of the filler itself, and the supporting structure of the chromatography system is reasonable. A qualified HPLC column evaluation report should provide the basic parameters, such as column length, inner diameter, column efficiency, etc.
Maintenance of HPLC columns
1. Use pre-column to protect analysis column; 2. The pH stability range of most reversed-phase chromatographic columns is 2~7.5; 3. Avoid drastic changes in mobile phase composition and polarity; 4. If a polar or ionic buffer solution is used as the mobile phase, the HPLC column shall be washed clean and stored in acetonitrile after the test;
Precautions for Use HPLC Columns
If you use You also can choose C8-Universal HPLC Column, CN HPLC Column, ODS C18 HPLC Column, Diol HPLC Column, and other HPLC Columns using, the correct use and maintenance of the HPLC chromatographic column are very important. Any carelessness will reduce the efficiency, shorten the service life or even damage the column. During the operation of the chromatographic column, the following issues need to be paid attention to. The chromatographic column has been maintained.
After the HPLC column is used for a period of time, there may be some strong adsorption substances remaining on the top of the column, especially some colored substances, which are easier to see on the packing that is adsorbed on the top of the HPLC column. After a new HPLC column is used for a period of time, the packing at the top of the column may collapse to restore the efficiency of the column. Therefore, after each work, it is best to wash with an eluent with a strong elution capacity. When using a salt buffer solution as the mobile phase, use a salt-free mobile phase to rinse after use. Compounds containing halogen elements may corrode stainless steel pipes and should not be in contact with them for a long time. If the column installed on the HPLC instrument is not used frequently, it should be turned on and flushed for 15 minutes every 4-5 days.
One is to avoid sudden changes in pressure and temperature and any mechanical vibrations. Sudden changes in temperature or dropping the chromatographic column from a height will affect the packing conditions in the column; a sudden increase or decrease in column pressure will also impulse the packing in the column. Therefore, the flow rate should be adjusted slowly.
The second is to frequently flush the chromatographic column with a strong solvent to remove impurities remaining in the column. When cleaning, the replacement of the mobile phase in the flow path system should be gradually transitioned with the solvent of the miscible solvent.
The third is to avoid directly injecting samples with a complex matrix into the column. It is necessary to pretreat the samples or connect a guard column between the injector and the chromatographic column.
Fourth, the chromatographic column cannot be repeatedly flushed, otherwise, the backflush will quickly reduce the column efficiency.