90um Dextran Gel Filtration Fillers G-25 F

90 μm Dextran Gel Filtration Media G-25 F

SHBC TopGF G-25 F is a fine-grade dextran gel filtration medium with a nominal particle size of 90 μm.

It is designed for protein desalting, buffer exchange and removal of salts or other low-molecular-weight substances from antibodies, antigens, enzymes and protein conjugates.

TopGF G-25 F is suitable for immunoassay development, biomolecule preparation and scalable biotechnology production.

TopGF G-25 F Technical Specifications

Size-Exclusion Separation Principle

TopGF G-25 F separates molecules according to their effective molecular size.

Large biomolecules are excluded from most pores and pass through the column first. Salts, free dyes and other small molecules enter the porous matrix and elute later.

Because the target biomolecule does not need to bind to the matrix, G-25 media can provide rapid group separation and buffer replacement.

Key Advantages of TopGF G-25 F

• Cross-linked dextran matrix

• Nominal 90 μm particle size

• Fine particle grade

• Efficient protein desalting

• Rapid buffer exchange

• Removal of low-molecular-weight impurities

• Separation without ligand binding

• Balanced flow and separation efficiency

• Suitable for antibodies and proteins

• Available for research and bulk production

Why Choose the 90 μm Fine Grade?

The fine particle format provides increased separation efficiency compared with larger-particle grades.

Potential advantages include:

• More uniform packed beds

• Improved separation of proteins from salts

• Efficient removal of small molecules

• Better fraction definition

• Suitable laboratory-scale purification

• Suitable process-development columns

Smaller gel filtration particles generally provide higher resolution, although they may create greater flow resistance than coarse media.

Immunoassay Manufacturing Applications

Antibody Desalting

TopGF G-25 F can be evaluated for removing salts and small buffer components from antibody preparations.

Typical applications include:

• Desalting after antibody purification

• Removal of ammonium sulfate

• Removal of reducing agents

• Cleanup after antibody concentration

• Preparation before conjugation

• Preparation before magnetic-bead coupling

Antibody Buffer Exchange

Antibodies can be transferred into a selected coupling, assay or storage buffer before:

• Epoxy magnetic-bead coupling

• Carboxyl magnetic-bead coupling

• Fluorescent labeling

• Enzyme conjugation

• Biotinylation

• Chemiluminescent labeling

• Immunoassay formulation

Antigen and Protein Preparation

TopGF G-25 F can also be evaluated for:

• Antigen desalting

• Recombinant protein buffer exchange

• Enzyme formulation

• Protein cleanup

• Removal of small reaction components

• Sample preparation before further chromatography

Removal of Free Labeling Reagents

TopGF G-25 F may be used to separate labeled proteins from smaller unreacted substances, including:

• Free fluorescent dyes

• Free biotin reagents

• Unreacted labeling reagents

• Reducing agents

• Buffer salts

• Small reaction by-products

G-25 Fine media are used in size-exclusion chromatography to remove excess dye from labeled proteins.

The process should be validated according to the molecular sizes of the labeled biomolecule and free reagent.

Suitable Samples

TopGF G-25 F can be evaluated with:

• Monoclonal antibodies

• Polyclonal antibodies

• Recombinant proteins

• Diagnostic antigens

• Enzymes

• Protein conjugates

• Labeled antibodies

• Labeled antigens

• Other water-soluble biomolecules

Performance depends on molecular size, sample concentration, viscosity, sample volume and column conditions.

General Operating Workflow

1. Hydrate the Medium

Hydrate the dry medium completely using purified water or the selected buffer.

Allow sufficient time for uniform swelling before packing the column.

2. Prepare a Uniform Slurry

Mix the hydrated medium gently to create a uniform slurry.

Avoid excessive air bubbles and strong mechanical shear.

3. Pack the Column

Transfer the slurry into a suitable chromatography column and allow the bed to settle evenly.

Avoid cracks, channels and trapped air.

4. Equilibrate the Column

Wash the packed bed with the target buffer until the outlet conditions are stable.

5. Load the Sample

Apply the sample evenly onto the column without disturbing the packed-bed surface.

6. Elute the Biomolecule

Elute with the target buffer. Larger biomolecules normally elute before salts and other small molecules.

7. Collect and Evaluate

Collect the target fraction and evaluate:

• Protein concentration

• Conductivity

• Recovery

• Buffer composition

• Purity

• Biological activity

• Immunoassay performance

Factors Affecting Separation Performance

Important factors include:

• Sample volume

• Bed volume

• Column dimensions

• Packed-bed quality

• Flow rate

• Protein concentration

• Sample viscosity

• Molecular-size difference

• Buffer composition

• Fraction collection volume

The sample-to-bed-volume ratio should be optimized to balance desalting efficiency, biomolecule recovery and sample dilution.

Column Packing Recommendations

For consistent results:

• Hydrate the medium completely.

• Prepare a uniform slurry.

• Remove trapped air before packing.

• Maintain a level bed surface.

• Avoid excessive compression.

• Prevent the packed bed from drying.

• Confirm stable flow before sample loading.

• Check the bed for cracks or channels.

Process Scale-Up

When transferring the process from laboratory testing to production, maintain consistent:

• Bed height

• Sample-to-bed-volume ratio

• Linear flow velocity

• Buffer composition

• Sample concentration

• Fraction collection strategy

• Cleaning procedure

• Product acceptance criteria

G-25 media are established for industrial desalting and buffer exchange because they can remove small contaminants and transfer biomolecules into a new buffer in one step.

TopGF G-25 F vs. G-25 M and G-25 C

Choose G-25 F when separation efficiency is the main priority. Choose G-25 M for balanced performance and G-25 C for faster bulk processing.

TopGF G-25 F vs. Dialysis

Desalting columns provide a rapid method for separating proteins and nucleic acids from salts and other small molecules.

Quality Control for Bulk Production

Recommended evaluation items include:

• Particle-size consistency

• Swelling consistency

• Packed-bed uniformity

• Flow performance

• Desalting efficiency

• Protein recovery

• Conductivity reduction

• Sample dilution

• Lot-to-lot consistency

• Storage stability

Why Choose SHBC TopGF G-25 F?

• Nominal 90 μm fine-grade particles

• Cross-linked dextran matrix

• Designed for desalting and buffer exchange

• Suitable for antibodies, antigens and proteins

• Supports immunoassay reagent development

• Samples available for evaluation

• Stable batch manufacturing

• Bulk packaging options

• Scalable production supply

• Technical support for grade selection

Storage and Handling

Store TopGF G-25 F according to the product label and technical documentation.

Recommended practices:

• Keep unused dry medium tightly sealed.

• Protect the medium from moisture and contamination.

• Use clean water, buffers and equipment.

• Avoid strong mechanical damage to hydrated particles.

• Do not allow the packed column to dry.

• Use a validated storage solution for hydrated media.

• Review the SDS before use.

Frequently Asked Questions

What is TopGF G-25 F?

TopGF G-25 F is a fine-grade cross-linked dextran gel filtration medium used for desalting, buffer exchange and group separation.

What is the particle size?

The nominal particle size is 90 μm.

What is the main application?

Its main applications are antibody and protein desalting, buffer exchange and removal of low-molecular-weight substances.

Can it purify antibodies directly?

It can desalt antibodies and replace their buffer. It does not replace affinity chromatography for selective antibody capture.

Can it be used before magnetic-bead coupling?

Yes. It can be evaluated for transferring antibodies or proteins into a compatible coupling buffer.

Can it remove free fluorescent dyes?

It may remove free dyes when they are sufficiently smaller than the labeled protein. Each labeling system should be validated.

Can it remove salts from proteins?

Yes. Under suitable column conditions, proteins elute before salts and other small molecules.

Is it suitable for high-resolution protein fractionation?

TopGF G-25 F is mainly designed for group separation, desalting and buffer exchange rather than detailed analytical fractionation.

What is the difference between G-25 F and G-25 M?

G-25 F uses smaller particles and is intended for improved separation efficiency. G-25 M provides a balance between flow rate and separation performance.

Is process optimization required?

Yes. Sample volume, bed volume, flow rate, buffer and fraction collection should be optimized for each application.

Can SHBC supply bulk quantities?

Yes. SHBC supports sample evaluation and bulk supply for research laboratories, immunoassay developers and biotechnology manufacturers.

Request TopGF G-25 F Samples

Contact Shanghai SanYu Biotechnology Co., Ltd. for samples, technical documentation and bulk quotations.

Please provide:

• Target biomolecule

• Current buffer

• Required new buffer

• Sample volume

• Protein concentration

• Column dimensions

• Required processing capacity

• Estimated annual demand

TopGF G-25 F is supplied for research and process development. Customers should validate the medium for their final manufacturing or diagnostic application.