Description
NAD+ is the oxidised form of nicotinamide adenine dinucleotide, a dinucleotide cofactor present in every living cell. It is built from a nicotinamide ring linked through two ribose sugars and a pyrophosphate bridge to an adenine. Molecular formula C21H27N7O14P2, molecular weight about 663.4 g/mol. Worth saying upfront because catalogues like to mix everything together: this is a coenzyme, not a peptide. There is no amino acid sequence and no SPPS process. It is purified as a sodium salt and lyophilised into a fine off-white powder.
Why it sits at the centre of so much metabolism research
NAD+ was first identified by Arthur Harden and William Young in 1906 while they were trying to figure out what was actually doing the work in yeast fermentation extracts. More than a century later it remains one of the most studied molecules in biochemistry, because almost every redox reaction in the cell routes electrons through the NAD+ / NADH pair. The ratio of those two forms is itself a readout of metabolic state, which is why labs working on mitochondrial function, glycolysis, and oxidative phosphorylation keep coming back to it.
Common research uses
- Enzymology assay substrate: NAD+ is the standard cosubstrate for hundreds of dehydrogenases, from LDH and ADH to GAPDH. NADH absorbance at 340 nm is one of the oldest quantitative readouts in biochemistry.
- Sirtuin work: SIRT1 through SIRT7 are NAD+-dependent deacylases. Without an NAD+ pool you have no sirtuin activity to study, which is why Sinclair lab style longevity papers all begin with NAD+ stocks on the bench.
- PARP and DNA damage research: Poly(ADP-ribose) polymerases consume NAD+ to ribosylate target proteins. PARP activity is usually quantified by NAD+ depletion.
- Cell-free metabolic reconstitutions: Synthetic biology groups use NAD+ as a regeneration cofactor in enzyme cascades.
Sourcing and identity
The NAD+ we list is supplied by a UK or EU manufacturer we have audited. We deliberately avoid unverified Chinese material on this one because NAD+ degrades into nicotinamide and ADP-ribose if it is handled badly during synthesis or shipping, and a freshly synthesised vial that looks fine on paper can actually be 70 percent intact NAD+ by the time it reaches your bench. The lots we ship test at 98 percent purity or higher by reverse-phase HPLC, with mass spectrometry confirming the 663 Da parent ion. The Certificate of Analysis you receive matches the lot number on the vial label. If the material does not match the CoA, we refund it.
Practical notes for the bench
NAD+ is hygroscopic and light-sensitive. Stored sealed at minus 20 C and kept away from moisture it is good for two years or more. Once reconstituted in water or buffer, aliquot it, freeze what you do not need that day, and avoid repeated freeze-thaw. Working solutions held at neutral pH and 4 C drift downward in concentration within hours, faster at higher pH, so pH 5 to 7 is the friendly window for assay buffers.
UK delivery and bulk
UK orders placed Monday to Thursday go out the same working day in light-protected, temperature-stable packaging. Around 90 percent arrive within 48 hours. If you need ten or more vials, or larger gram quantities for a cascade or screening project, message support and we will quote a price rather than ask you to stack the cart. Live chat during UK hours is staffed by actual people, not a bot, and the same team handles CoA questions and reconstitution queries.
Sold strictly for in vitro laboratory research. Not for human or veterinary use. UK 18+.

