Electrophoresis is a chemical process in which charges in a solution flow toward opposite electrodes. In the 1930s, Swedish biophysicist Arne Tisselius developed electrophoresis while studying blood proteins. In 1948, Arne Tisselius was awarded the New Prize in Chemistry for his contribution to the technique of electrophoresis.
Gel electrophoresis is one of the laboratory methods for separating DNA, RNA, or protein molecules based on their electric charge or size.
How Does Gel Electrophoresis Work?
The principle behind electrophoresis is the observation that most biomolecules exist as charged particles with ionizable functional groups. Depending on the pH, a solution containing biomolecules will have either positively or negatively charged ions.
When charged molecules are placed in an electric field, they travel in the opposite direction to the positive or negative pole. Depending on the mass and net charge of each particle in solution, ionized biomolecules will migrate at different rates when exposed to an electric field.
Negatively charged particles, such as nucleic acids, are drawn toward the anode, while positively charged particles move toward the cathode. Due to changes in speed and direction, each charged particle will migrate in a pattern determined by its specific properties, allowing the separation of biomolecules with similar properties.
Types of Gel Electrophoresis
They are also classified as native and denatured, in which the RNA or protein retains its native structure as it passes through the gel in native gel electrophoresis. In contrast, in denaturing gel electrophoresis, RNA or protein is reduced to a linear structure before or during gel electrophoresis. This reduction is accomplished by adding a reducing agent to the sample, gel, and/or buffer, which cleaves bonds within the RNA or protein molecule and leads to the formation of secondary structures. Below, we outline the main types of gel electrophoresis that buyers typically ask about, along with their practical applications.
1. Based on Gel Matrix
Paper Gel Electrophoresis
One of the earliest methods, paper electrophoresis is still used in some clinical labs to study serum proteins and other body fluids. It is non-toxic, easy to store, and relatively low-cost. However, its poor conductivity, protein adsorption, and background staining often lead to poor resolution. The hydroxyl groups in cellulose slow down protein migration, causing band tailing. From a supplier’s view, this method is now more of a niche request, mainly for teaching purposes or basic clinical demonstrations.
Agarose Gel Electrophoresis (AGE)
Agarose remains a workhorse in DNA and RNA analysis. Its gel concentration controls resolution, making it suitable for separating DNA fragments ranging from 100 bp to 20 kb. Beyond nucleic acids, agarose can also be used for protein separation and even isoelectric focusing when prepared at very low concentrations. Because agarose gels are inexpensive, safe, and versatile, suppliers often recommend them to academic labs, molecular biology facilities, and routine testing labs.
Polyacrylamide Gel Electrophoresis (PAGE)
PAGE gels, prepared at concentrations of 3–30%, offer precise control over pore size. Proteins typically require higher concentrations, while DNA/RNA needs lower ones. Customers value PAGE for its accurate porosity and reproducibility, making it indispensable for applications like DNA sequencing, RNA analysis, molecular weight estimation, and recombinant DNA studies. Since acrylamide is toxic, suppliers usually suggest pre-cast gels or enclosed gel systems for safety and convenience.
2. Based on Denaturing Conditions
Native Gel Electrophoresis
This method keeps proteins or nucleic acids in their natural structure, allowing researchers to study biological activity, interactions, or conformations. Buyers in biochemistry or enzymology fields often prefer native systems, because they want more than just a “band pattern” — they need functional insights.
Denaturing Gel Electrophoresis
In contrast, denaturing gels use chemical agents like SDS (for proteins) or urea/formamide (for nucleic acids) to unfold molecules. This ensures separation is based mainly on molecular size, which is critical when customers are focusing on accurate protein molecular weight determination. From a supplier’s perspective, we often bundle these systems with compatible buffers and reagents, since proper chemical handling ensures consistent results.
3. Specialized Gel Electrophoresis Techniques
SDS-PAGE
Perhaps the most common method for protein analysis. By coating proteins with SDS, charges are equalized, so proteins separate only by size. Most pharmaceutical companies and life science research institutes rely on SDS-PAGE to confirm protein purity or monitor expression levels. For customers scaling up protein work, we usually suggest electrophoresis systems that can run multiple gels simultaneously.
2D Gel Electrophoresis (Two-Dimensional)
A more advanced technique combining isoelectric focusing (based on pH) and SDS-PAGE (based on size). This method allows separation of thousands of proteins in a single run. Customers from proteomics and drug discovery often request 2D systems, and as suppliers, we typically recommend bundled imaging equipment to complement the gel unit.
Pulse Field Gel Electrophoresis (PFGE)
Designed for very large DNA molecules, such as whole microbial genomes. PFGE equipment is less common but essential for public health labs and food safety agencies. From a supply side, PFGE units are larger, require precise cooling, and need longer run times — so we guide customers to plan for adequate space and power supply.
Capillary Gel Electrophoresis (CGE)
A modern, automated version of electrophoresis that uses narrow capillaries filled with polymer gels. This technique offers high resolution, speed, and digital output, making it popular in clinical diagnostics and sequencing labs. Suppliers often highlight CGE systems for labs that prioritize automation and data accuracy.
Isoelectric Focusing (IEF) and Blue Native PAGE (BN-PAGE)
Both specialized systems for protein research. IEF separates proteins by isoelectric point, while BN-PAGE is useful for studying large protein complexes in their active forms. Customers in structural biology and membrane protein research usually request these setups, and we advise them on accessories like gradient makers and high-quality buffers.
| Type | Main Application | Key Advantage |
| Agarose Gel Electrophoresis (AGE) | DNA/RNA analysis (PCR checks, cloning) | Easy, low cost, broad fragment range |
| Polyacrylamide Gel Electrophoresis (PAGE) | Small DNA/protein separation | High resolution |
| Native Gel Electrophoresis | Functional protein/nucleic acid studies | Preserves biological activity |
| Denaturing Gel Electrophoresis | Size-based protein/nucleic acid separation | Accurate molecular weight determination |
| SDS-PAGE | Protein purity/size | Standardized, reliable |
| 2D Gel Electrophoresis | Complex proteome analysis | High-resolution, dual separation |
| PFGE | Large DNA fragments, genome mapping | Handles megabase DNA |
| Capillary Gel Electrophoresis (CGE) | DNA sequencing, clinical testing | Automated, high accuracy |
| Isoelectric Focusing (IEF) / BN-PAGE | Protein charge and complex studies | Specialized protein analysis |
Application of Gel Electrophoresis
Electrophoresis plays a role in nearly every area of life sciences, from diagnostics to research.
- Clinical Diagnostics – Protein and enzyme profiling, immune-electrophoresis, and disease marker identification.
- Molecular Biology and Genetics – PCR verification, cloning, sequencing, and genetic engineering studies.
- Proteomics and Biochemistry – Protein purity checks, structural analysis, and proteome mapping.
- Food Safety and Microbiology – PFGE for microbial tracking and outbreak analysis.
- Forensics – CGE for DNA fingerprinting and evidence analysis.
Advantages of Gel Electrophoresis
Gel electrophoresis remains popular because of its clear benefits:
- High resolution and sensitivity for detecting even small molecular differences.
- Versatility in separating DNA, RNA, proteins, and antigens.
- Scalability from classroom teaching kits to advanced proteomics platforms.
- Cost-effectiveness of entry-level agarose systems.
- Flexible readout options — from visual staining to fully digital results.
- Reproducibility and standardization, ensuring global consistency in regulated industries.
Despite rapid advances in genomics and proteomics technologies, gel electrophoresis remains important in laboratory analysis. Its balance of affordability, reliability, and scalability ensures ongoing demand across teaching institutions, research labs, clinical diagnostics, food safety, and forensics.
From a supplier’s perspective, success lies in offering not just the instrument but a complete workflow solution — including gels, buffers, staining kits, and imaging systems — so that laboratories can fully harness the power of electrophoresis. If you have any laboratory equipment needs, please feel free to contact us.
Related Products Recommendation
What Next?
For more information, or to arrange an equipment demonstration, please visit our dedicated Product Homepage or contact one of our Product Managers.
