copurified

Copurified is an adjective used in chemistry, biochemistry, and related fields to describe substances that are purified together with another compound during an isolation procedure. Copurification often arises when the compounds share similar chemical properties, such as polarity, charge, or molecular size, and interact with the purification matrix or elute together. The resulting purified fraction contains the target compound along with accompanying substances.

In protein purification, copurified proteins may reflect stable protein–protein interactions or non-specific binding to the affinity resin. In chemical and analytical workflows, copurified contaminants, solvents, or salts may accompany the target, complicating quantitation and downstream analyses. In environmental analysis and pharmacology, copurification of matrix components can interfere with detection methods, requiring additional cleanup or orthogonal instrumentation.

Managing copurification involves adjusting purification strategy to separate the target from contaminants, such as using orthogonal purification steps, altering buffer composition, pH, or salt concentration, and employing higher-resolution techniques. In some contexts, copurified partners are of interest because they indicate biological interactions and provide insight into protein complexes or pathways. Proper documentation and analytical validation are needed to distinguish genuine copurified entities from artifacts.