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Cat. No.: G25MN-5 (for 5 pcs)

Cat. No.: G25MN-20 (for 20 pcs)

Description

G-25 Mini Desalting Column is a pre-packed ready-to-use chromatography column designed for simple, rapid, and efficient separation of large molecular weight substances from small molecular weight substances using G-25 Medium (G-25 M) matrix. Commonly referred to as a desalting column, it is primarily used to remove salt ions, detergents, small molecule dyes, buffer components, and other impurities from samples such as proteins, nucleic acids, peptides, and polysaccharides. The packing material used in this desalting column is G-25 Medium with a particle size range of 70-250 μm, capable of separating proteins or other large molecules with a molecular weight greater than 5 kDa. The column bed volume is 2.1 ml, with a recommended sample volume of 0.1-0.5 ml. The functionality and usage of this product are consistent with Cytiva's PD MiniTrap G-25 and are suitable for gravity flow or centrifugation methods.

The G-25 Medium matrix used in this product is a high molecular weight polymer with a three-dimensional porous structure formed by crosslinking dextran with epichlorohydrin as the crosslinking agent through ether bonds, similar to the performance of Sephadex G-25 Medium. When separating samples using this product, larger molecules cannot enter the porous structure of the matrix and are retained outside the gel matrix. As the elution solution flows through the interstices between the gel particles, larger molecules are washed out of the column first due to their faster downward movement, while smaller molecules or ions can enter the porous structure of the matrix and remain inside the gel for a longer period. Consequently, smaller molecular weight substances have a slower elution rate and are washed out of the column later. This separation and purification method is known as size-exclusion chromatography (SEC), also commonly referred to as molecular sieve chromatography (MSC) or gel filtration chromatography (GFC).

Basic Information

Features

• This desalting column has wide applications, effectively removing salt ions, detergents, small molecule dyes, buffer components, and other impurities from samples. It can be used for desalting proteins, nucleic acids, peptides, polysaccharides, etc., completing solution exchange; removing phenol red from culture media to facilitate subsequent protein or nucleic acid purification by ion exchange chromatography; removing nucleotides from DNA samples for subsequent DNA sequencing; removing small molecular weight markers from samples; terminating reactions between large and small molecules; removing products of protease, cofactors, or inhibitors; removing excess radioactive labels from DNA labeling reactions; removing excess biotin (D-Biotin) from in vitro biotinylation reactions.
• This desalting column offers significant advantages over traditional dialysis methods using semi-permeable membranes. 
  • It provides fast separation and saves time: the desalting column can rapidly separate samples, typically processing one sample in just 5 minutes, whereas dialysis with semi-permeable membranes typically takes at least 6 hours. 
  • It is suitable for small volume operations with high sample recovery rates: the desalting column can effectively handle small volume samples ranging from 0.1-0.5ml, with a recovery rate usually exceeding 90%. In contrast, during dialysis with semi-permeable membranes, some samples may adhere to the membrane during sample release, leading to incomplete recovery, hence not suitable for small volume samples. 
  • It saves solution usage: dialysis with semi-permeable membranes requires a large amount of buffer solution, whereas the desalting column only requires 10ml of buffer solution to complete the experiment.
• This desalting column offers two usage methods: gravity flow and centrifugation, which can be selected according to experimental requirements.
  • Gravity flow: Samples pass through the desalting column by gravity, offering simplicity in operation and low equipment requirements. The sample recovery rate is slightly higher than centrifugation, but the sample undergoes approximately 1.4 times dilution.
  • Centrifugation: Samples pass through the desalting column under centrifugal force. Although the sample recovery rate is slightly lower than gravity flow, the sample remains undiluted.

Storage

Stored at 4ºC, valid for two years. Stored at room temperature, valid for at least one month.

Precautions

• To prevent cross-contamination, it is recommended to use this product only once.
• Repeated use of the desalting column may lead to decreased sample recovery rates.
• Do not freeze this product as freezing may cause fragmentation of the desalting column matrix.
• During storage and purification processes, keep the matrix moist at all times to avoid air bubbles entering the desalting column.
• It is recommended to add 25mM NaCl to the buffer solution to prevent potential ion interactions. If NaCl cannot be used, try adding 100mM ammonium acetate (NH4Ac) or 100mM ammonium bicarbonate (NH4HCO3) volatile buffer solutions.
• When the salt concentration in the buffer solution is >1M, the residence time of hydrophobic substances in the column may be prolonged or may bind to the matrix.
• When the buffer solution contains >1.5M (NH4)2SO4, the desalting column matrix may shrink.
• This product is intended for scientific research use by professionals only and is not intended for clinical diagnosis or treatment, food, or drug use. Do not store in residential areas.
• For your safety and health, wear lab coats and disposable gloves during operation.

Related:

• G-25 Spin Desalting Column
• G-25 Mini Desalting Column
• G-25 Midi Desalting Column
• G-25 Max Desalting Column

Only for research and not intended for treatment of humans or animals