HPLC Guard Column Manufacturer

HPLC Guard Column Manufacturer

Top Quality 316L HPLC Guard Column Manufacturer


What is Guard Column in HPLC system ? 

With the increase of the usage time of the HPLC column, the separation efficiency of the column decreases and the column pressure increases mainly because the HPLC column head is contaminated, while the whole column bed of the column is still not seriously damaged.

Suppose a short column can be added to the front end of the column, allowing all contamination or damage to occur here, thus protecting the relatively expensive column.

In that case, this is the original design intent of the guard column and the role of the column. Usually, the packing material packed in the guard column is the same or similar to that of the chromatographic column, and the particle size of the packing material can be slightly larger considering the price and other factors during use;

the role of the guard column is to protect the hplc column, so its size is not very important.


As follow is the Working Principle of HPLC Guard Columns, Please check it. 


Working Principle Of HPLC Guard Column


The guard column generally adopts the structure of interchangeable cores so that when the sample is not clean, causing contamination of the guard column, or when starting another work that requires another type of column, it is only necessary to replace the core with a guard column, which is extremely convenient to use. Moreover, the ferrule-type guard column can be tightly attached to the column head, thus further eliminating the dead volume between the guard column and analytical column.


HPLC Guard Column Category

Column Holders are divided into split columns and direct-connected columns. Separate columns are used in series with PEEK or stainless steel connectors fitting (connectors + tubing) and columns, while direct-connected guard columns can be directly connected in series with columns.

uHPLCs as a professional HPLC Guard Column Manufacturer introduces a series of guard column products, including guard holders and guard column cartridges.

Connecting the guard column in series to the front of the column can efficiently reduce column contamination, prolong column life, and reduce column wear and tear costs.

guard column chart


Why Do l Need a Precolumn?

A pre-column or guard column protects the main column from plugging and contamination by samples and the mobile phase. We recommend using a precolumn, stand-alone design because it is easy to replace and generates less charge for you than replacing the main column. But: A precolumn never substitute the necessary sample pretreatment.


How to Choose a Guard Column in HPLC Without Affecting the Separation Analysis?

Usually, the first thing to consider before selecting a guard column is whether the sample is clean or not. For most analysts, a 1 cm column will provide adequate protection. However, if the sample is very unclean, or if the work reveals that the 1 cm guard column must be replaced frequently, then a 2 cm or 3 cm long guard column should be selected.

The principle of selecting a column is to choose the shortest possible column and to use packing material that retains as little of the sample to be separated as possible, provided that the analytical separation requirements are met.


If You Also Interested to the HPLC Guard Column For Your HPLC Experiment Project, Or

You Like to Wholesale HPLC Guard Column, Welcome to Send email to contact us by sales@uhplcslab.com

 You can also send inquiry to our contact page. we will get back to you within 48-Hours


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What is a guard column, and why is it necessary?


A guard column is a small column installed between the sample injection port and the analytical column in chromatography. The guard column serves as a sacrificial column, meaning that it is intended to protect the analytical column from contamination and sample matrix effects. 

The guard column is typically filled with the same stationary phase as the analytical column, which will help to retain any unwanted contaminants or matrix components that may interfere with the separation of the target analytes. Guard columns are available in a variety of sizes and materials, and they can be easily replaced or cleaned when they become saturated or fouled.

The use of a guard column is essential for maintaining the performance and longevity of the analytical column in chromatography. Without a guard column, contaminants in the sample matrix can accumulate on the analytical column over time, leading to increased baseline noise, reduced column efficiency, and ultimately, the need for more frequent column replacement. So you can know, By using a guard column, the analytical column is protected from these contaminants, and the cost and time associated with column replacement can be minimized.



Why Use HPLC Guard Column ?  


After using the hplc guard column, especially when the sample is not very clean and there is a need to reconnect it after disassembly,

please pay attention to the connection direction when it is used. Otherwise, it is easy to cause the contamination of the column head

of the guard column to enter the column with the mobile phase, it will lead to contamination of the column head, and the guard column

will naturally fail to perform its protective function. The same applies to the use of copper HPLC columns.


The connection of the guard column is also very important. The shorter the connection line between the chromatographic column and

the guard column, the better, and the inner diameter of the connection tube should be as small as possible.



When to Replace the Guard Columns?

The guard columns should be replaced when one of the following conditions is met 

a. The theoretical column number of the chromatographic column has decreased by more than 15%.
b. The pre-column pressure of the chromatographic column increases by more than 15%.
c. The resolution of the most difficult to separate substances decreases by more than 15%.
d. The number of sample injections exceeds 150.
e. The mobile phase passes through 1500 times the volume of the column.


So you can check and get the fast quotation of uHPLCs' guard columns HPLC , our engineers will supply you

with a good solution and price within 48-Hours. 

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Guard Columns or Guard Column Cartridges Replacement Procedure:

1. disconnect the liquid chromatography column from the guard column and replace the guard column (or column core)
2. Replace the guard column (or remove all tape from the guard column core, replace the core, and connect the guard column)
3. Rinse the replaced guard column with methanol for 30 minutes.
4. connect the HPLC column


Do The Pre-column and Guard Column Refer to the Same Component?

Do They Have the Same Construction, Principle, and Function?

The guard column is connected to the column after the injector and before the column. Its purpose is to protect the column, especially the column head, from being scrapped due to contamination.

The pre-column appears later. It is also to protect the column, but mainly to prevent the dissolution of the mobile phase to the column, especially the extreme pH damage. Its packing is consistent with the hplc column by being dissolved to saturate the mobile phase and no longer react with the hplc column, it is connected between the pump and the injector.


Precautions for the Use of Guard Columns:

1. When connecting the guard column and analytical column, the connecting pipeline should be as short as possible. The interface should be smoothly cut to minimize the dead volume and reduce the column spreading effect.

2. The commercially available guard column is generally not marked with the direction of liquid flow. uHPLCs provide the service of marked direction, which can avoid contamination of the analytical column by entrained impurities when used in the forward and reverse directions.

3. The direct connect guard column, column pressure rise or peak shape deterioration can not be connected to the analytical column for reverse cleaning. Cleaning solvent can refer to the analytical column cleaning solvent.

4. Guard cartridge replacement, pay attention to the core and column sleeve to determine whether there is a directional match, while not easy to screw too tight to prevent slippery wire.

5. The guard column or guard cartridge is generally not recommended for ultrasonic cleaning because it may impact the packing surface modification.

6. The same guard column with a different analytical column, each time before use, the guard column should be cleaned and mobile phase equilibrium guard column for some time, and then connected to the analytical column use.


How do I choose the right guard column and analytical column for my application?

Actually, Choosing the right guard column and analytical column for a particular chromatographic analysis is a complex process, because it requires you consider several factors, including the sample matrix, the analytes of interest, and the desired separation efficiency etc

First, When you to select a guard column, it is important to choose a column that is compatible with the stationary phase of the analytical column, as well as one that has a similar particle size and packing material.

The Second important factor you should care is account the expected matrix effects and the expected level of contamination from the sample. Different guard column configurations, such as guard cartridges or guard columns with replaceable frits, can also be selected based on the specific application needs.

The Third, The selection of an analytical column also requires us to consider the sample matrix and the analytic of interest. Factors such as sample complexity, analytic polarity, and temperature requirements can all influence the choice of analytical column. It is important to choose a stationary phase that is appropriate for the chemical properties of the analytic and to select a particle size that balances the need for separation efficiency with the need for analysis speed.


How do I maintain and replace a C18 guard column?

Proper maintenance and replacement of the C18 guard column are essential for maintaining the performance and longevity of the analytical column for each experimenter. Because the guard column should be inspected and replaced or cleaned regularly to prevent contamination from building up on the analytical column. But the frequency of replacement or cleaning will depend on the sample matrix, the number of samples analyzed, and the column usage conditions.

To replace a C18 guard column, some steps you'd better to check and follow:

1. First, Disconnect the guard column from the analytical column and dispose of it properly.

2. Second, Before Installation a new guard column, making sure to use the appropriate fittings and column orientation.
Flush the guard column with the mobile phase to remove any air pockets and allow it to equilibrate before beginning the analysis.
To clean a C18 guard column, the following steps can be followed:

3. Disconnect the guard column from the analytical column.
Flush the guard column with a suitable solvent, such as methanol or acetonitrile, to remove any contaminants.
Flush the guard column with the mobile phase to remove any residual solvent.
Reconnect the guard column to the analytical column and allow it to equilibrate before beginning the analysis.



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