Definition

Noun: A method for determining the concentration or potency of a substance by measuring its effect on a living organism or biological system, compared to a standard preparation.

Usage

A bio-assay is a scientific procedure. It is used primarily in pharmacology, toxicology, and environmental science to evaluate the strength or biological impact of substances like drugs, hormones, vitamins, or pollutants.

Examples

• The laboratory conducted a bio-assay to measure the potency of the new antibiotic.
• Standardized bio-assays are essential for ensuring the consistency of vaccine batches.
• Researchers used a plant growth bio-assay to test the soil for herbicide contamination.

Advanced Usage

• In vivo bio-assay: An assay conducted within a living organism (e.g., testing a drug's effect in mice).
• In vitro bio-assay: An assay conducted in a controlled environment outside a living organism (e.g., using cell cultures or tissue samples).
• The term is often used in regulatory contexts to describe mandatory tests for product safety and efficacy.

Variants and Related Words

• Bioassay (noun): A common alternative spelling without the hyphen.
• Biological assay (noun phrase): The full term.
• Assay (noun/verb): A broader term for analyzing a substance to determine its composition or quality. A bio-assay is a specific type of assay.

Synonyms

• Biological test
• Biotest

Notes on Meaning

The core meaning of bio-assay is the quantitative assessment of a substance's biological activity. It is distinct from a chemical assay, which analyzes chemical structure or purity. The result of a bio-assay is often expressed in units of biological activity.

Noun

1. appraisal of the biological activity of a substance by testing its effect on an organism and comparing the result with some agreed standard