Used in molecular biology for gel electrophoresis of nucleic acids. Provides a stable pH environment that allows DNA and RNA to migrate through agarose or polyacrylamide gels. The buffer conducts electric current necessary for separation while protecting the integrity of nucleic acids during the run. Commonly used in DNA fragment analysis, PCR product verification, and restriction enzyme digestion checks. Offers better resolution and buffering capacity compared to other systems like phosphate buffers. Often reused for multiple runs due to stability, though fresh preparation is recommended for sensitive applications.