DL-β-Leucine is used in biochemical research as a non-proteinogenic amino acid to study metabolic pathways and enzyme specificity. It serves as a building block in the synthesis of peptides and peptidomimetics with modified structures, which can enhance stability or alter biological activity. It is also employed in the development of pharmaceutical intermediates, particularly in drugs targeting neurological and metabolic disorders. Due to its structural similarity to natural amino acids, it can act as a probe in studies involving amino acid transport systems and neurotransmitter regulation. Additionally, DL-β-Leucine finds use in cell culture media formulations to support the growth of specific microorganisms or mammalian cells under controlled conditions.