Dilution assay

Dilution Assay

A Dilution Assay is a biological assay technique used to determine the concentration of a substance in a solution. It is often used in microbiology, immunology, and pharmacology to measure the potency of antibodies, antigens, and drugs.

Overview

In a dilution assay, the substance of interest is diluted in a series of steps, each dilution being tested for its effect. The concentration at which a specific response is observed is then used to calculate the concentration of the substance in the original solution. This method is particularly useful when the substance is too concentrated to measure directly.

Procedure

The procedure for a dilution assay involves several steps:

1. Preparation of Dilutions: The substance is diluted in a series of steps, typically in a serial dilution format. Each dilution is usually a factor of 10 or 2 less concentrated than the previous one.
2. Testing of Dilutions: Each dilution is tested for its effect. This could involve observing the growth of microorganisms, the binding of antibodies to antigens, or the physiological response to a drug.
3. Determination of Concentration: The concentration at which a specific response is observed is used to calculate the concentration of the substance in the original solution.

Applications

Dilution assays are used in various fields of biological and medical research:

• In microbiology, they are used to determine the concentration of bacteria or viruses in a sample.
• In immunology, they are used to measure the potency of antibodies or antigens.
• In pharmacology, they are used to determine the concentration of drugs in a solution, and to measure the potency of drugs.

See Also

• Biological assay
• Serial dilution
• Microbiology
• Immunology
• Pharmacology