Operation and maintenance methods of the hottest l

2022-09-23
  • Detail

Use and maintenance methods of liquid chromatograph

pay great attention to the use of liquid chromatograph:

when using ferrule column, the ferrules at both ends should be connected to the column core at all times. No matter you are balancing the chromatographic column or cleaning, you should not remove the ferrule at any time, otherwise it will cause the loss of packing

precautions for the use of liquid chromatography column:

a. installation of ferrule column (pre column)

1. Put the ferrule frame into the column core

2. Insert the two jacketed pieces into the groove of the column core so that the jacket is higher than the column core

3. Push the ferrule frame that has been sleeved on the column core upward until it is higher than the jacketed piece

4. Put the bullet head pre column into the ferrule piece

5. Screw the ferrule cap and the ferrule frame together, Then tighten it by hand

6. Then connect the other end of the column in the same order

b. the balance chromatographic column

reverse phase chromatographic column is stored in acetonitrile/water after factory test. Please make sure that the mobile phase you use is miscible with acetonitrile/water. It is not allowed to tighten the anchor nut and start the testing machine. Because the chromatographic column may dry out during storage or transportation, this testing machine conforms to the standard gb/t2976 ⑵ 004/iso 7802:1993 "test method for wire entanglement of metallic materials". Methanol or acetonitrile balance chromatographic column with 10-20 times the column volume should be used before analyzing samples with mobile phase; If the mobile phase you use contains buffer salt, you should pay attention to the transition with pure water. This method greatly simplifies the operation process of verification

silica gel column or polar chromatographic column is stored in n-heptane after factory test. If the chromatographic column needs to use an aqueous mobile phase, please balance it with ethanol or isopropanol before using the mobile phase

how to balance the chromatographic column

in the process of balancing, slowly increase the flow rate and balance the chromatographic column with mobile phase until a stable baseline is obtained (if the buffer salt or ion pair reagent degree is low, it will take a long time to balance)

regeneration of chromatographic column

when regenerating chromatographic column, a modest pump should be used. We suggest that it is best not to use the pump on your HPLC

note:

when regenerating the NH2 modified chromatographic column, NH2 may exist in the form of ammonium ions, so it should be washed with 0.1M ammonia after water washing, and then washed with water until the alkali solution completely flows out. If the impurities adsorbed on the silica gel surface cannot be completely washed away by simple organic solvent/water treatment, washing with 0.05m dilute sulfuric acid is very effective

maintenance of chromatographic column:

1. Use pre column to protect the analytical column (silica gel has a certain solubility in polar mobile phase/ionic mobile phase)

2. The pH stability range of most reversed-phase chromatographic columns is 2-7.5, Try not to exceed the pH range of the chromatographic column

3. Avoid drastic changes in the composition and polarity of the mobile phase

4. The mobile phase must be degassed and filtered before use

5. If polar or ionic buffer solution is used as the mobile phase, the column stopper and rotary table should be cleaned without damage and cracks after the experiment, and stored in acetonitrile

6. The pressure rise is a signal that the pre column needs to be replaced

Copyright © 2011 JIN SHI