Types of Electrophoresis

Introduction

Types of electrophoresis are classification of the processes involves during application of electrical energy to any substance. Electrophoresis is derived from two Greek words, elektron means amber and phoresis means the act of bearing. In 1931, the first work of electrophoresis begins by Arne Tiselius. It was a primitively easy of separating the chemical and molecules analysis. The modern version of this process starts in the 21^st century.

What is Electrophoresis?

Electrophoresis is a method and technique used for separating the RNA, DNA, and protein molecules. The whole process is done on the basis of size of the molecules and the electrical charge. For separating the molecules, one kind of electrical current is used and a gel medium is needed.

Figure 1: Application of Electrophoresis

Bensaccount at English Wikipedia, SDS-PAGE Electrophoresis, CC BY 3.0

The electrophoresis process is used in many sectors, such as −

• Antibiotics are now one of the most used medical assistance to help patients in fighting the illness. Electrophoresis is used for antibiotic testing.

• The most used sector of Electrophoresis is DNA analysis.

• It is helpful in the vaccine testing.

• Electrophoresis is used to analyse the proteins and the antibodies.

Principle of Electrophoresis

There is a separate principle of electrophoresis works on. The charged macromolecules are placed in the electrical field that helps to move the direction of the positive and negative poles. The movement is dependent on the macromolecules are already charged. For example, a nucleic acid is one kind of particle of negatively charged, it tends to move the direction toward the anode.

Figure 2: How Electrophoresis works

The two types of electrophoresis process are available, which are: capillary electrophoresis and slab electrophoresis. In the process of separation the protein, if it is already negative, then it moves to the anode and if it is positive then moves to the cathode. Scientists can measure the distance travelled by the molecules because smaller molecules can move faster than larger molecules and the size of the molecules is determined with help of logarithms.

The electrophoresis works on the basis of fundamental equation of electromagnetism, which provides it with a form, and it can be represented as,

$$\mathrm{F = qE}$$

Where F is the force, q is the electrical charge and E is the strength of electricity.

The equation simply means the higher charged particles have a stronger force when the electric field is applied. It means two molecules that have equal mass will move at the same time with different charges.

Types of Electrophoresis

The modern process of Electrophoresis has a supporting media, which helps to separate the charged molecules. It has two major functions, one is to sieve the molecule and the other is the absorption for separation. Two types of Electrophoresis method arementioned below as follows −

Capillary Electrophoresis or CE

This method required sub-millimetre diameter capillaries and micro and nano-fluidic channels. These analytes migrate through the electrolytic solution which influence and help to separate them on the basis of the movement of ions and partitioning into another phase.

Slab Electrophoresis or SE

This type of method is used to separate the protein. At a time, many samples are analysed with the help of 1D format. SE is much simpler method than the CE because, the CE needs proper instruments and set up whereas the SE needs nothing as such.

There are some other types of electrophoresis mentioned below −

• Gel Electrophoresis- It is considered the most used process of electrophoresis. In this process, three kinds of gel are used such as: starch, polyacrylamide, and agarose.

• Paper Electrophoresis- It is one of the simplest forms of electrophoresis. One kind of strip of paper is used in this method.

• Zone Electrophoresis- It is used for the analysis of nucleic acids, biopolymers, and proteins.

• Immunoelectrophoresis- This process is a combination method of electrophoresis and immune-diffusion.

Procedure of Electrophoresis

Electrophoresis of a DNA requires a few steps such as −

• Preparation the sample.

• In the next step the agarose TAE gel solution is prepared.

• Gel casting is one of the most important steps.

• Setting up the electrophoresis chamber.

• The next step is Gel loading.

• The process of Electrophoresis starts.

• Observe the DNA and make notes.

• The last step is to expose the ethidium bromide stained gel under UV light for taking a picture.

Conclusion

The electrophoresis method is completely laboratory-based, and referred to as the movement of colloidal particles. The gel is used in the process has pores which allow the smaller molecule of the mixture to move faster than the larger-sized molecule. The condition that is used in the process can be adjusted according to the requirement of separating the molecules.

FAQs

Q1. What is the basic principle of Electrophoresis?

Ans. The principle of electrophoresis is the migration of a changed species in a supporting medium, which can be fluid or gel. This occurs under the influence of an electric field”.

Q2. What method of Electrophoresis is used for DNA?

Ans. In the laboratory, gel electrophoresis is used for the DNA. It helps to separate them according to the molecular size from a mixture of DNA, proteins or RNA. These methods need an electrical field to get into the small pores.

Q3. What is the importance of pH in Electrophoresis?

Ans. The pH is important in electrophoresis because if pH level changes in the subject, then the structure and charge of the protein are also changed. It affects the whole process and the proper separation does not take place.

Q4. What is the difference between electrophoresis and immuno-electrophoresis?

Ans. Electrophoresis is a process of migration of electrically charged molecules through a gel base with the influence of electric field. On the other hand, immuno-electrophoresis is a method where the combination of protein electrophoresis and an antigen-antibody is required for separating the mixture of protein.