What is NAD+?

Is NAD+ a peptide?

No. NAD+ (nicotinamide adenine dinucleotide) is not a peptide and contains no amino acids or peptide bonds at all. It is a dinucleotide: a molecule made of two nucleotides joined together, one built around an adenine base and the other around a nicotinamide group, linked through a pair of phosphate groups. This puts it in an entirely different chemical class from the peptide compounds discussed elsewhere on this site, even though it is often sold alongside them as a research compound.

The distinction matters because peptides and coenzymes are studied using different methods and are involved in different kinds of cellular processes, even where their research areas sometimes overlap, such as in studies of cellular ageing and metabolism.

NAD+ as a redox coenzyme

NAD+ functions as an electron carrier in cellular metabolism. In its oxidised form, NAD+, it accepts a pair of electrons (and a hydrogen) during key metabolic reactions such as glycolysis and the citric acid cycle, becoming NADH, its reduced form. NADH then donates those electrons onward, most notably to the electron transport chain in mitochondria, where that electron flow is coupled to the production of ATP, the cell's main energy currency.

This constant cycling between NAD+ and NADH is one of the most fundamental reaction pairs in cellular biochemistry, which is why NAD+ availability is studied across a very wide range of metabolic research, not just in one specific area.

Sirtuins, PARPs and CD38

Beyond its role as an electron carrier, NAD+ is also consumed as a substrate, rather than just cycled, by several enzyme families that are widely studied in cellular biology research.

• Sirtuins: a family of enzymes studied for their role in deacetylating proteins, a reaction that consumes NAD+ and is examined in research on cellular stress responses and gene expression regulation.
• PARPs (poly-ADP-ribose polymerases): enzymes studied in the context of DNA damage detection and repair signalling, which use NAD+ as a substrate to build poly-ADP-ribose chains.
• CD38: a cell-surface enzyme studied as one of the major consumers of NAD+ in mammalian cells, relevant to research on how NAD+ levels decline with cellular age in laboratory models.

The NAD+/NADH ratio

Because NAD+ and NADH are interconverted continuously, researchers often look at the ratio between the two rather than the absolute amount of either one. This ratio is used in laboratory studies as an indicator of a cell's overall redox state and metabolic activity, and changes in the ratio are examined in research spanning metabolism, mitochondrial function and cellular stress.

How NAD+ is supplied as a research compound

NAD+ used in research is manufactured and supplied as a purified biochemical, characterised in the same way as other research compounds, typically with purity assessed by HPLC and identity checked by mass spectrometry or against a reference standard. Celyfe's published NAD+ certificate (batch A26085) is an HPLC report from a third-party laboratory, Analiza Białek in Wrocław, dated 2 October 2026, on a sample Celyfe supplied. It reports 99% chromatographic purity and a measured content of 182.93mg/ml, about 110% of the 166.7mg/ml label. It does not include mass spectrometry. The Celyfe NAD+ Precision Pen supplies 500mg of NAD+ per 3ml cartridge, dispensing 1.667mg per 0.01ml click across 300 clicks, shipped cold-chain and stored refrigerated between 2 and 8 degrees Celsius, in line with the same in-solution stability principles that apply to peptide cartridges.

Research use only

NAD+ supplied by Celyfe is intended for laboratory and research use only. It is not a licensed supplement or medicine, and nothing here describes or implies its use in or on a human or animal body.