Buy SS-31 25mg Online

SS-31 (elamipretide, CAS 736992-21-5, C32H49N9O5, molecular weight 639.78 Da) is a four-residue peptide with the sequence H-D-Arg-Dmt-Lys-Phe-NH2, where Dmt is 2,6-dimethyltyrosine, developed by Hazel Szeto and Peter Schiller. Its alternating aromatic and cationic residues give it an unusual property: it crosses cell membranes without a transporter and concentrates in the inner mitochondrial membrane at roughly a thousandfold over cytosolic concentration, without depending on membrane potential the way most mitochondrial-targeting compounds do. Once there it binds cardiolipin, a four-tailed phospholipid found almost exclusively in that membrane. Cardiolipin is not structural padding — it is required for the assembly and stability of respiratory chain supercomplexes, the physical association of Complexes I, III and IV that keeps electrons moving efficiently between them. When cardiolipin is peroxidised by reactive oxygen species, supercomplexes come apart, electron leak rises, and more ROS are produced, closing a damaging feedback loop. By binding cardiolipin, SS-31 stabilises the supercomplexes and protects cardiolipin from peroxidation; reported reductions in mitochondrial ROS in stressed cardiomyocytes and neurons run to roughly 30 to 50 percent.