![HPLC Column](img/common/cat_title.gif)
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SILICA for high performance liquid chromatography is filled with precisely classified high-quality spherical silica and features excellent pressure resistance and separation performance.
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1. Operating Procedure
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1.
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Prepare a mobile phase for use. After degassing completely, filtrate the mobile phase using a membrane filter 0.45 µí or smaller to remove dust. A 2-µí filter is used at the column inlet. To prevent foreign matter from clogging
the column inlet filter, we recommend using a line filter. . Do not use a water-type solvent.
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2.
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Before attaching the column, replace the liquid in the instrument with the mobile phase to be used. Especially, after reversed-phase runs, remove water completely out of the instrument.
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3.
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Connect the column as shown in Fig. 1. . The arrow on the column indicates the mobile phase flow direction. . The column joint is of the male nut type for piping of 1/16 inch OD. Check that the piping joints of the system
fit correctly and that the ferrule tips are deeply inserted into the joints. (See Fig. 1.)
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4.
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Allow the mobile phase to remain at a flow rate of about 1 mL/min and wait until the baseline stabilizes. Compared with a reversed phase column, the SILICA column takes time to equilibrate. Start analysis after the baseline
becomes sufficiently stable.
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5.
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Prepare a sample solvent from an appropriate solvent and start analysis. . Dissolve the sample in a solvent of the same composition as the mobile phase wherever possible. . Using a solvent with strong dissolving power may
lower the separation efficiency or cause the sample to precipitate at the column head. . If there is insoluble matter remaining in the sample solution, filtrate the solution using a filter 0.45 µí or smaller.
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2. Notes on Use
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1.
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Handling the Column To prevent column deterioration, avoid the following. In addition, attach or detach the column when the pressure gage indicates zero. . Frequent change of the mobile phase composition or direct change
to a mobile phase of low compatibility . Rapid change in column inlet pressure . High column pressure due to the use of a high-viscosity mobile phase
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2.
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Storing the Column . Seal the column with the accessory plug and store it in a cold place where there is little temperature fluctuation. . For storage with a volatile solvent, take precautions to ensure that the packing
material will not dry out. Any impact after evaporation of the solvent will damage the packing condition and cause peak splitting or plate number loss.
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3. End Fittings
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1.
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An analytical column of up to 4.6-mm ID uses a filter-embedded end fitting as shown in Fig. 1. The filter cannot be changed alone. If the filter is clogged or the column pressure is high, replace the end fitting. See Table 1 for
the replacement parts and repair items.
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2.
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See Fig. 1 for the column connection. If the tubing is inappropriate, especially if a tube for a different type of column is used, the length after the ferrule tip (V in Fig. 1) is often different from the end fitting length L, and
a problem may occur. If L is greater than V, dead volume may be generated and cause peak broadening or tailing or deterioration of separation performance. If L is smaller than V, liquid may leak because of inadequate ferrule
adhesion.
Therefore, we recommend replacing the ferrule together with the column. *If the column is replaced frequently, the male nut may crush the ferrule and liquid may leak. Since tightening the nut too much may cause its head
to come off, replace the ferrule at an early stage.
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【Fig. 1】 Column connection
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4. Replacement Parts and Repair Items
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Table 1 Replacement parts and repair items
Part No.
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Part Name
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Description
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EF21105
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End fitting (4.6 mm)
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2 pieces
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EF21103
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Piping kit(2pcs)
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Male nuts (1/6) and ferrules (1/16) 2pieces each
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EF21110
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Ferrule (1/16)
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Ferrules (1/16)10pieces
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5. Troubleshooting
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Problems in high performance liquid chromatography are attributable to various causes that cannot all be enumerated. The table below describes some comparatively common problems related to the column.
Symptom
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Cause
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Measures
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Blocking with foreign matter
1.
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Dust or insoluble matter in the mobile phase or sample solution.
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2.
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Dirt in the tubing.
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3.
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Plunger seal fragment.
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4.
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Precipitation of sample components.
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Sonicate the filter or replace it.
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Filtrate the mobile phase and sample solution in advance using a membrane filter.
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Attach a line filter.
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Clean the tubing and replace the plunger seal.
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Prepare a sample solution with the mobile phase.
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2.
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Peak splitting, tailing, and broadening.
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1.
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Void in the column head.
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2.
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Dead volume due to inappropriate connections.
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3.
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Inappropriate mobile phase conditions.
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Ion suppression method: Inadequate suppression (Too much sample).
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Ion-pair method: Inadequate concentration of the ion-pair agent (Too much sample).
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4.
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Column deterioration.
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*
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Not repairable in the case of column deterioration or damage to the packing condition.
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Replenish the packing material.
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Reconnect the tubing.
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Review the pH, salt concentration, sample amount, and other conditions.
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Review the ion pair agent concentration, pH, sample amount, and other conditions.
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Check the column performance using standard inspection solution.
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3.
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Retention time too long or unstable.
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1.
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Liquid leak (Indicated on the pressure gage of the pump).
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2.
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Inappropriate mobile phase conditions.
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3.
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Inadequate column equilibration time.
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Check the pump and tubing for any leaks.
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See 2-3.
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Secure adequate equilibration time.
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4.
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Retention time too short.
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1.
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Hydrolysis (deterioration) of a bonded groups by strong acid or base.
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2.
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Inappropriate mobile phase conditions.
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3.
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Inadequate column equilibration time.
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See 2-3.
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Secure adequate equilibration time.
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SILICA is shipped after a strict performance check. However, if you should find any defect, please contact your dealer or Osaka Soda for replacement. Note that Osaka Soda does not warrant the product against column life or deterioration
caused by the failure to follow the above handling instructions. Ten or more days after reception by the customer, Osaka Soda will assume that the product was delivered in good condition, and will not accept a later replacement
request.
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