Gel Electrophoresis

Gel Electrophoresis is one of the zone electrophoresis, and the supporting medium of it is gel. The gel is a cross-linked polymer, acting as a molecular sieve. Its composition and porosity are chosen based on specific requirements. The types of gel typically used are starch, agarose, and polyacrylamide gels.

Starch: Partially hydrolyzed potato starch is a non-toxic medium for the separation of non-denatured proteins.

Agarose: Agarose is a purified uncharged polysaccharide extracted from seaweeds. By manipulating the concentration of agarose in the gel, the pore size can be adjusted. Agarose gel electrophoresis is suitable for the separation of proteins larger than 200 kDa, and DNA fragments of 0.2-20kb.

Polyacrylamide: Polyacrylamide gel is tougher than agarose gel and is relatively inert, thermostable, strong, and transparent, with a uniform pore size. Polyacrylamide gel electrophoresis (PAGE) is suitable for the separation of proteins from 5 to 2,000 kDa.

Sodium dodecyl sulfate-polyacrylamide: Sodium dodecyl sulfate (SDS) is added to PAGE. SDS-PAGE eliminates the influence of structure and charge in electrophoresis, and proteins are separated based on the differences in their molecular weight. It is suitable for the separation of proteins from 5 to 250 kDa.

Fig.1 Illustration of gel electrophoresis

• Preparation
  Prepare electrophoresis buffer with a certain pH. Prepare a gel solution of appropriate concentration, taking care not to produce bubbles, and use a cast to solidify the solution into a gel.
• Sample Application
  Put the prepared gel with a cast into the electrophoresis tank, and add an appropriate amount of buffer. Pipette the sample into the sample wells.
• Electrophoresis
  Adjust the appropriate distance between the electrodes. Switch on the electrophoresis apparatus and set the voltage and current. Perform electrophoresis for a period of time.
• Determination
  After electrophoresis, stain the gel for visible results. Observe, record and analyze the position of separated bands. Or, utilize an imaging system for analysis.
• Downstream processing
  After separation, an additional method is often applied to the separated bands for further processing. For example, cut the band out of the gel as a slice to dissolve and purify it.
  Notes: Part of the solution involved in this experiment is toxic. Please handle it carefully with gloves.

• Sharp zones
• Better resolution
• Good recovery of proteins and reasonable yield
• Less adsorption of proteins
• Less time consumption
• Easy preparation
• Stability of gel over a wide range of pH and temperature
• Downstream processing

• Separation of proteins
• Separation of DNA fragments for extraction or purification
• Estimation of the DNA concentration and the size of DNA molecules
• Estimation of molecular weight of nucleic acids and proteins
• Analysis of PCR products
• Identification of disulfide bonds between proteins
• Checking the purity of proteins
• Separation or characterization of metals or metal oxide nanoparticles

Electrophoresis Systems

An electrophoresis system applies an electric charge to molecules, causing them to migrate toward their oppositely charged electrode. It’s the device for electrophoresis performing and is usually divided into horizontal type and suspension type. The choice of electrophoresis systems depends on the molecule of study, the method of separation and the downstream application.

Electrophoresis Accessories

We provide comprehensive electrophoresis accessories including electrophoresis power supplies, combs, UV blocking mats, exposure cassettes, gel cutting tools, short plates, spacer plates, and so on, for gel preparation and electrophoresis performance in electrophoresis experiments.

pH Meters

A pH meter is an instrument used to determine the pH value of a solution, utilizing the relationship between the electromotive force of the galvanic cell and the hydrogen ion concentration. A pH meter is used to determine the pH value of buffers in electrophoresis experiments. The temperature and ionic strength should be considered in pH measurement.

Gel Drying Equipment

We provide gel drying equipment with drying frames, assembly table, cellophane, gel drying solution, and other accessories to dry the microgel between two sheets of cellophane, for the preservation of polyacrylamide and agarose gels. Once dry, the gel is clear with a glossy finish and is ideal for use in density measurements or as a photographic record for long-term storage in a lab notebook.

Pipettes

Pipettes are used to aspirate and dispense larger and specific amounts of liquid. They made be reusable or disposable, made from glass or plastic (typically polystyrene), nonsterile, sterile, or autoclavable, and cotton-plugged or plain. Accurate liquid measurements, dilutions, and transfer is key to most successful laboratory assays and analyses.

Staining Appliances

We provide Gel Staining Boxes made from translucent polypropylene or clear PMP with snap-fit lids. Drain located flush with the bottom minimizes disturbance of the gel during liquid drainage. The box can be used to stain, fix, destain and manipulate gels and membranes conveniently in electrophoresis experiments.

Transilluminators

A transilluminator is an instrument that produces strong white, blue, and/or UV light for use in medical examinations, viewing electrophoresis gels, autoradiographic films, and other clinical and laboratory procedures. We provide Ultra Violet Transilluminators with large surface areas and high sensitivity for viewing electrophoresis gels in electrophoresis experiments.

Digital Gel Imaging Systems

A digital gel imaging system combines a high-resolution camera and professional image analysis software to help you easily perform chemiluminescence and fluorescence imaging as well as analysis of western blots and gels. In electrophoresis experiments, it is mainly used for nucleic acid or protein electrophoresis observation, photography, and scientific analysis of experimental results.

Chemiluminescence Imaging Systems

An automatic chemiluminescence imaging system is a fully automatic computer-controlled professional shooting and analysis system for real-time high-definition dynamic imaging. It is used for chemiluminescence detection of Western Lightning, ECL\ECL plus, CDP-Star, SuperSignal, CSPD, LumiGLO, and other luminescent substrates.

Fluorescent Imaging Systems

A fluorescent imaging system usually includes a high-resolution camera, a human user interface, an imaging workstation, and professional software. We provide fluorescent imaging systems with extremely low noise, fast frame rate, wide dynamic range, high quantum efficiency, high resolution, and a large field of view, to help you with the analysis of experimental results.

STEMart provides you with a variety of electrophoresis equipment or consumables to meet your various R&D and application needs. If you have any questions or requirements for gel electrophoresis, please feel free to contact us.