With the passage of time and the increasing number of injections, the HPLC column may generally be a decrease in efficiency when the peak height decreases, the peak width increases, or the shoulder peak appears.
1.Reversed-phase column regeneration
Take a solvent such as methanol: water = 95: 5 (VA’_), pure methanol, di-methane, etc. as a mobile phase, sequentially flush, and each mobile phase is passed through the column and recorded as 20 to 30 times the column volume and then the column is washed in the reverse order.
2.Normal phase column regeneration
Sequentially flush the column with n-hexane, isopropanol, di-methane, and methanol as the mobile phase. Pay attention to the order of the equilibrium solvent in each step. Do not invert the flow of each mobile phase through the column for 20 to 30 column volumes (due to the higher viscosity of isopropyl alcohol, please pay attention to adjust the flow rate during the flushing process), rinse with methanol, and then flush the column in the reverse order. The above solvents must be strictly dehydrated.
3.Ion exchange column regeneration
Prolonged use in high pH and high ion strength buffer solutions will result in reduced column ion exchange capacity. The cation column can be regenerated by rinsing with a dilute acid buffer solution; on the contrary, the anion column can be regenerated by rinsing with a dilute alkali buffer solution.
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