NAD+ (nicotinamide adenine dinucleotide, oxidized form) is not a peptide — it is a dinucleotide coenzyme, one of the most fundamental molecules in biochemistry, and it appears in research-supply catalogs because the study of NAD+ metabolism has become one of the largest fields in cell biology. Every redox-dependent pathway in central metabolism uses the NAD+/NADH couple, and beyond redox chemistry the molecule is the consumed substrate of three heavily studied enzyme families: the sirtuins, the PARPs, and the CD38/NADase group. That substrate role — NAD+ as something cells spend, not just cycle — is what turned it from a textbook cofactor into an active research area.
Research background
Two threads dominate the literature. The first is classical enzymology: NAD+ as the electron carrier of glycolysis, the TCA cycle and oxidative phosphorylation, where it is interconverted with NADH rather than consumed. The second, more recent thread is NAD+ consumption and biosynthesis — how cellular NAD+ pools are maintained through salvage pathways, how the consuming enzymes draw those pools down, and how pool changes propagate through the pathways that depend on them. Research catalogs stock the molecule because both threads need it as a substrate, a standard, and a supplement to in vitro systems. Note the relationship to 5-Amino-1MQ elsewhere in this catalog: NNMT, the enzyme that compound inhibits, sits adjacent to the same salvage pathways — the two are catalog neighbours for a reason.
Structure and analytical profile
NAD+ is a dinucleotide — adenine and nicotinamide, each on a ribose, joined through a pyrophosphate bridge — with a molecular weight of approximately 663.4 g/mol. Analytically the questions are identity, purity, and oxidation state: NAD+ and NADH are distinct species with distinct spectra (NADH absorbs at 340 nm; NAD+ does not), which gives laboratories a clean way to characterize what a lot actually contains. Hydrolysis products from moisture exposure are the characteristic impurities.
Verifying a lot
Lot number matching the vial, a named issuing laboratory with the original report attached, a report verifiable at the source. Certificates for every NAD+ lot we sell are published in the certificate archive.
Handling notes
Store cool, dark and, above all, dry — the pyrophosphate linkage hydrolyzes with moisture, and solutions are markedly less stable than the solid. For qualified laboratory settings only.
Frequently asked research questions
Is NAD+ a peptide? No — it is a dinucleotide coenzyme. It shares catalog space with peptides because NAD+ metabolism is one of the most active research areas the catalog serves.
What is the difference between NAD+ and NADH? Oxidation state: NAD+ is the oxidized form, NADH the reduced. They are interconverted in redox reactions and distinguishable by absorbance at 340 nm.
What should an NAD+ certificate show? Identity consistent with ~663 g/mol, purity, lot number, issuing laboratory and report date; characterization of hydrolysis impurities is a mark of a thorough report.
All products discussed are for laboratory research use only and are not for human or veterinary consumption. Nothing here describes or endorses any use in humans or animals.