It is well-known that HPLC column has a limited lifetime. As time goes by in use, its performance begins to decline. You can tell it from the peak shape and separation between peaks, the irregular increasing of column back-pressure and the presence of ghosting peaks. Chromatographic columns are expensive chromatographic consumables, which need to be maintained after normal use. If the performance of a column does deteriorate, what can be done to recover it?
At first, if the column scales due to overload or the use of incompatible mobile phases, it can be recovered. However, columns that have been damaged or have passed the service life cannot be recovered and need to be replaced.
The restore procedures of HPLC column are as follows:
Reversed-phase column
Inverse phase separation is the main mode of operation used in most HPLC separations. The packing is mainly composed of C18, C4, CN, NH2 and phenyl stationary phase. It is recommended that the order of water – acetonitrile – isopropanol – heptane – isopropanol – acetonitrile – mobile phase be eluted with 10 to 20 times the volume of solvents.
Normal phase column (amino, diol, nitro, amino stationary phase)
Rinse with 20 times of the volume of solvents according to the order of heptane – isopropanol – acetonitrile -water, isopropanol, heptane.
GPC / GFC
GPC / GFC Chromatographic Column
Flush with 5 times of volume and 0.1% phosphate buffer at pH 3. If retention proteins are used, a 60-minute gradient of water to acetonitrile to water is used.
The performance of chromatographic columns should be investigated before they are used. Also check again during use or after placing for a period of time and save the results. Column performances include column pressure under certain experimental conditions (sample, mobile phase, flow rate, temperature), theoretical plate height and plate number, repeatability of symmetry factor, capacity factor and selectivity factor, or separation degree. When comparing the column effect, we should also pay attention to whether there is any change in the outside column effect. But please note that column performances may vary depending on the sample used, mobile phase, column temperature, and other conditions. In addition, the column performance test was conducted according to the conditions in the factory report of the column (the conditions used in the factory test were the best conditions). Only in this way can the measured results be comparable.
UHPLCs chromatographic column is made of stainless steel. The inner wall of the stainless steel column is polished to reduce the wall effect and improve the column efficiency. The column is filled with bonded silica gel or polymer fillers. Chromatographic column is based on high purity silica gel, using unique bonding technology with excellent peak shape and good sensitivity. The content of matrix metals is low and the peak shape of all analytes is intact. High mechanical strength, good stability and strict quality control ensures the performance of the column and the service life of the column. A variety of sizes are available to suit the different needs of chromatographers and their applications. 
Post time: Mar-13-2021
