What is the primary use of test tube brushes in the lab?

Test tube brushes are primarily designed for cleaning test tubes. Their bristle structure allows them to reach into the narrow confines of test tubes effectively, enabling the removal of residues, stains, or any other contaminants that may be present. This is essential in a laboratory setting, where maintaining cleanliness is crucial for obtaining accurate results and preventing cross-contamination of samples.

Other tools in the laboratory serve different purposes, such as holding chemicals (which would require containers), mixing solutions (which could utilize stirrers or shakers), and measuring liquids (usually done with graduated cylinders or pipettes). Each of these has a specific design that optimizes it for its respective function, whereas test tube brushes are uniquely suited for ensuring that test tubes are thoroughly cleaned and ready for reuse.