L-Carnitine + B12 10mg/10mL

This is a multi-component aqueous reference solution. Its constituents span several chemical classes: a betaine-class zwitterion (L-carnitine), two proteinogenic amino acids (L-arginine and L- methionine), a cyclitol (myo-inositol), a quaternary ammonium cation (choline), the alcohol analogue of pantothenic acid (dexpanthenol), a pyridine-ring vitamer (pyridoxine) and a cobalt-centred corrinoid (cyanocobalamin). None of the constituents is a peptide.

Each constituent is characterised against its own defined in-vitro system rather than as a single target. L-carnitine is the acyl-acceptor substrate in carnitine palmitoyltransferase 1 (CPT1) initial-rate enzyme assays using recombinant enzyme or isolated mitochondrial preparations. Cyanocobalamin is the precursor cofactor form assayed in methionine synthase (MTR) and methylmalonyl- CoA mutase (MMUT) activity measurements. Pyridoxine is assayed as the precursor of the pyridoxal-5′- phosphate cofactor in transaminase activity assays. Reported values are enzyme kinetic constants measured in these preparations.

Primary literature covers the analytical chemistry of each constituent — chromatographic separation of quaternary ammonium and zwitterionic species, and spectrophotometric determination of corrinoid and pyridine vitamers. Search results and cited literature do not establish the performance of a commercial lot or a use recommendation.