L-Carnitine

L-Carnitine (CAS 541-15-1, C7H15NO3) is an endogenous quaternary ammonium compound biosynthesised from lysine and methionine in the liver and kidneys. Its primary metabolic function is to shuttle long-chain acyl-CoA esters from the cytoplasm across the inner mitochondrial membrane via the carnitine-acylcarnitine translocase (CACT) system — a step that is rate-limiting for beta-oxidation of long-chain fatty acids. Without L-Carnitine, long-chain fatty acids cannot reach the mitochondrial matrix for oxidation. In research, L-Carnitine is used as the primary substrate in CPT1 enzyme assays, fatty acid oxidation models, and metabolic flux experiments. For research use only.

L-Carnitine is the base form responsible for mitochondrial fatty acid transport — the standard research substrate for CPT1 assays and beta-oxidation studies. Acetyl-L-Carnitine (ALCAR) is an acetylated form that crosses the blood-brain barrier more readily; it is additionally studied for its role in acetyl group donation to acetylcholine synthesis in neuronal models. L-Carnitine-L-Tartrate is a salt form with improved aqueous solubility commonly used in sports science research. Our product is L-Carnitine (the free zwitterionic inner salt form) — the appropriate choice for mitochondrial fatty acid transport, CPT1 enzyme kinetics, and acylcarnitine profiling research. Not for human consumption — for research use only.

L-Carnitine is used across many cell-based and biochemical models: skeletal myocyte and cardiomyocyte fatty acid oxidation assays; CPT1 and CPT2 enzyme activity assays; acylcarnitine profiling via LC-MS/MS — a standard assay for fatty acid oxidation disorders; mitochondrial membrane potential studies using fluorescent probes; Seahorse XF metabolic flux analyser experiments (as supplementary substrate); carnitine deficiency rescue experiments in carnitine-depleted cell lines; and hepatocyte lipid accumulation models (NAFLD research). Not for human consumption — for research use only.

Reconstitution: L-Carnitine is highly water-soluble. Draw the required volume of bacteriostatic water or sterile buffer and inject into the vial; swirl gently until dissolved. For 500mg vial: 5mL = 100mg/mL; 10mL = 50mg/mL; 50mL = 10mg/mL. L-Carnitine solution is relatively stable — refrigerate at 2–8°C and use within 4 weeks. Unlike glutathione, L-Carnitine has no significant oxidation concerns at normal handling temperatures. Store lyophilised powder at −20°C.

L-Carnitine is legal to purchase in Australia for legitimate laboratory research purposes. As an endogenous compound naturally present in meat and biosynthesised by the human body, it is not a scheduled substance when sold for research use. Purchasers must confirm research-only use. Our L-Carnitine 500mg is supplied as a research compound with >99% HPLC purity. Peptide Warehouse Australia dispatches nationwide from our Melbourne warehouse via Australia Post. Not for human consumption in this lyophilised research form.

The carnitine shuttle moves long-chain fatty acids (>C12) across the inner mitochondrial membrane in three steps: CPT1 (outer membrane) converts long-chain acyl-CoA + L-Carnitine → acylcarnitine + CoASH; CACT (translocase) moves acylcarnitine into the mitochondrial matrix while transporting free carnitine out; CPT2 (inner membrane) converts acylcarnitine + CoASH → acyl-CoA + L-Carnitine, releasing the fatty acid for beta-oxidation. This shuttle is rate-limited by available L-Carnitine and CPT1 activity. CPT1 inhibitors (e.g. malonyl-CoA) and L-Carnitine supplementation are standard tools for studying mitochondrial fatty acid flux. Not for human consumption — for research use only.

L-Carnitine is also known as levocarnitine. For in-vitro research use only.