#3 How Do You Care for Your Chromatography System?
Occasionally check your UV detector lamp life to ensure it meets recommended output parameters.
Tubing on your chromatography system should be short enough to minimize dead volume while allowing component positioning flexibility.
Buffer lines should be cleaned with purified water at the end of the day. This is especially important when working at low temperatures where salts can precipitate.
Always degas or vacuum filter buffers prior to use to minimize air and particulates in your mobile phase.
Occasionally inspect buffer bottles/bags for signs of bacterial growth. Solutions that appear cloudy upon shaking or stirring should be discarded. Treatment with a bacteriostatic agent such as 0.02% sodium azide will prolong solution storage.
It is recommended to replace your piston washing solution weekly with fresh 20% EtOH or isopropyl alcohol. At minimum, regularly inspect for fluid level depletion or bacterial growth.
Sample inlet lines and sample loops should periodically be cleaned with 1 N NaOH solution, followed by water or neutralizing buffer, to eliminate sample buildup in the tubing.
Periodically replace PEEK* tubing that comes in regular contact with sample, especially lines connected to your fraction collector.
Storing all system lines in fresh 20% EtOH when not in use is an effective way to avoid bacterial growth. It is recommended that this is done at the end of each work day.
Injection needles are best used with volumes of 1 ml or less. Larger volumes can be more easily managed with a luer fitting attached to your injection port.
Calibrate your pH probe daily for most accurate results. Electrodes should always be stored in their designated storage solution or a neutral buffer. 20% EtOH should not be used, as it changes the concentration of KCl in the probe.
Pre-equilibrate the selected column prior to running and observe UV/conductivity behavior stability. Many automated systems allow you to advance to sample injection once complete equilibration is observed.
Periodically check system tubing for cracks and bends. Tubing bends can restrict flow and increase system backpressure.
For best results, occasionally sanitize your entire system with 1 N NaOH to clear the flow path from pump to fraction collector.