L-Arginine methyl ester dihydrochloride is widely used in biochemical research as a precursor for synthesizing peptides and proteins. It serves as a building block in solid-phase peptide synthesis, enabling the creation of specific amino acid sequences. This compound is also utilized in studying enzyme mechanisms, particularly those involving arginine-specific enzymes, due to its structural similarity to L-arginine. Additionally, it is employed in pharmaceutical development for designing drugs that target nitric oxide pathways, given its role in nitric oxide production. In cell culture studies, it acts as a supplement to support cell growth and protein expression. Its stability and solubility make it a practical choice for various experimental applications in molecular biology and medicinal chemistry.