electrophoresis

Electrophoresis is a separation technique that uses the charge and mobility of ions to separate molecules in the liquid state. This study contributes to Moscow State University’s Ferdinand Frederic Reuss, who detected an electric field motion of clay particles in water. This technique forms the basis for analytical methods used in chemistry for separating molecules. Electrophoresis is used to identify source DNA in forensic science and paternity testing.

Define Electrophoresis

Electrophoresis refers to a scientific technique that uses an electric field to segregate molecules in a fluid or a gel. Generally, Electrophoresis is used in procedures to distinguish macromolecules such as RNA, proteins, DNA, nucleic acids, plasmids, and fragments of macromolecules. Simply, it describes the motion of particles in a fluid or gel within a relatively uniform electric field. It separates molecules based on their size, charge, and binding affinity. 

Use of Gel Electrophoresis 

Gel electrophoresis is a typical lab practice used to separate charged molecules such as DNA, RNA, and proteins according to their size. Critical use of gel electrophoresis list is given below.

• It helps study the structure and functions of the protein.

• This technique is helpful in the analysis of antibiotic resistance.

• While investigating crime scenes, this process helps separate DNA fragments for DNA fingerprints.

• It is also helpful in analysing the results of polymerase chain reactions.

• Helpful in analysing genes associated with any particular illness or disease.

• Helps analyse macromolecules in blotting techniques.

• It helps check the quality and quantity of genomic DNA after DNA extraction.

• It helps in getting a DNA fingerprint for paternity testing.

How does Electrophoresis work?

When two electrodes are submerged in water and an electric field is applied across it, the particles present in the solution tend to move towards one or the other electrode based upon their charge. Such movement is because the macromolecules are already electrically charged, which forces them to cause motion in the electric field. 

Here, the particles with a positive charge move towards the cathode, and particles with a negative charge move towards the anode. These positively charged particles are cations, whereas negatively charged particles are anions. The processes are called cataphoresis and anaphoresis, respectively.

Types of Electrophoresis

1. Capillary Electrophoresis: 

Depending upon the size and charge of the particle, charged particles are separated with this technique. It requires the help of various migration rates present in the electric field to separate the charged particles with this technique.

• Gel Electrophoresis: This is the most preferred electrophoresis procedure. There are a total of three categories of gel electrophoresis. These are:  polyacrylamide gel, starch gel and agarose gel electrophoresis. Starch gel electrophoresis uses granules of potato starch as a corroborative medium. 

A completely cleansed polysaccharide is used as support media in agarose gel electrophoresis in a large molecular mass. When it comes to polyacrylamide gel electrophoresis, it functions on a huge molecular concentration batch.

• Paper Eletrotropherosis: This is the most straightforward technique of Electrophoresis. The sample needs to be separately printed on a paper. Further, it includes dipping the end of this paper on buffer solutions for moisturising it. Then the application of an electric current to the paper takes place. The current emphasises the sample to stride in the electrode direction with the opposite polarity. After this process is conducted, the paper is dried and observed using a premium detection system.

1. Slab Electrophoresis: 

Compared to Capillary Electrophoresis, Slab Electrophoresis is a popular procedure because it needs no specific instruments. In this process, one can quickly analyse many samples simultaneously with the help of a 1D format. It can be further divided into three styles of electrophoresis process. They are as follows.

• Zone Electrophoresis: This electrophoresis process includes the transportation of various samples within a buffer structure under the electric current. It is a process for analysing nucleic acid, proteins and biopolymers. As there is a difference between the mobilities, these molecules will segregate into appropriately resolved and assorted peaks.  

• Immunoelectrophoresis: This process is the mixture of two methods; electrophoresis and immune-diffusion. Immunoelectrophoresis involves placing an antigen mixture into wells cut in gel without any antibodies and separating their components through the electrophoresis process.

• Isoelectrofocusing: Charged macromolecules such as peptides and proteins are separated with the process of Iso Electrofocusing. This separation is based on their pH and the piezoelectric point where the molecule doesn’t contain any charge or is neutral. In this process, the macromolecules present in the gradient of pH move to their electric field. 

Conclusion

To conclude, the term electrophoresis simply portrays the migration of charged particles under the influence of an electric field. Depending upon the charge of such particles, it either migrates to the cathode or anode. This theory is based upon the fact that different molecules have different natural electric charges associated with them, which causes the movement of different molecules at different rates under an electric field.