Immunoelectrophoresis is a biochemical technique which is used for the separation and identification of proteins, mainly immunoglobulins in biological samples. It is a combined method of electrophoresis and immunodiffusion. In this technique, proteins are first separated in agarose gel by applying electric current. After separation, specific antibody is added into the gel. The separated proteins … Read more
Ouchterlony Double Immunodiffusion Method is a qualitative immunological technique that is used to study antigen–antibody reaction in vitro. It is the process in which both antigen and antibody are allowed to diffuse freely in a semi-solid medium usually agar or agarose gel. This method was developed by Örjan Ouchterlony and it is commonly used for … Read more
A blood smear is a simple diagnostic preparation where a drop of peripheral blood is spread on a clean slide, and it is dried for staining. It is the process used for observing blood cells and also for detecting parasites after staining methods like Giemsa. It is an important technique because it helps in demonstrating … Read more
Latex agglutination test is a simple serological test where antigen and antibody reaction is made visible on the surface of latex particles. It is the process in which latex beads are coated either with antigen or with antibody and when a sample containing the corresponding component is added, the beads is clumped together forming visible … Read more
Single Radial Immunodiffusion also referred to as Mancini technique is a quantitative immunodiffusion technique that is used to measure the antigen’s concentration by measuring the size of the precipitin-based ring created by the interaction between the antigen with the antibody at the optimal concentration. The antibody is embedded in the agarose gel, while the antigen is diffused into it in the form of a radiatal pattern.
What is Rapid Plasma Reagin (RPR) Test? Principle of Rapid Plasma Reagin (RPR) Test The principle of the Rapid Plasma Reagin (RPR) test is based on the detection of antibodies produced in response to antigens released by damaged host cells during a syphilis infection. The RPR test is a macroscopic, non-treponemal flocculation card test that … Read more
What is Mantoux Test? Principle of Mantoux Test The Mantoux test operates on the principle of delayed-type hypersensitivity, specifically Type IV hypersensitivity. This test is designed to assess a person’s cell-mediated immunity against the bacterium Mycobacterium tuberculosis. To conduct this test, a substance known as Purified Protein Derivative (PPD) is used, which is essentially a … Read more
What is Neutralization Test? Principle of Neutralization The neutralization principle is based on the understanding that certain antibodies or antitoxins can reduce or neutralize the various biological effects caused by enzymes, toxins, and viruses. There are two main types of neutralization tests: In both types of neutralization tests, the goal is to assess the ability … Read more
What is Complement Fixation? Principle of Complement Fixation Test The principle of the complement fixation test is based on the interaction between antigens, antibodies, and complement proteins. When an antigen and antibody come into contact, they form an antigen-antibody (Ag-Ab) complex. This complex then interacts with complement proteins and becomes fixed with them. As a … Read more
Such is the case with the slide and tube Widal test. The agglutinins against the ‘0’ (somatic) and ‘H’ (flagellar) antigens of Salmonella typhi, paratyphi A, and paratyphi B are measured qualitatively (slide test) and quantitatively (Tube test) using a suspension of suitable organisms that have been killed. Widal-quantitative tube agglutination test This test aids … Read more
