NAD+ (Nicotinamide Adenine Dinucleotide)

NAD+ (nicotinamide adenine dinucleotide) is a pyridine dinucleotide coenzyme, not a peptide. It is built from two nucleotides, one carrying a nicotinamide base and one carrying adenine, joined through a pyrophosphate bridge. The molecule exists in an oxidized form, written NAD+, and a reduced form, written NADH, and the pair functions as a hydride carrier in cellular redox chemistry. Its molecular formula is C21H27N7O14P2 and its molecular weight is 663.43 g/mol. Because it contains no chain of amide-linked amino acids, NAD+ sits outside the peptide class entirely and is treated in the literature as a nucleotide cofactor.

Published biochemistry assigns NAD+ two distinct roles. As a redox coenzyme it cycles between NAD+ and NADH through glycolysis, the tricarboxylic acid cycle and oxidative phosphorylation, and it is not consumed during that cycling. As a consumed substrate it is cleaved by sirtuins, poly(ADP-ribose) polymerases and CD38, which detach the nicotinamide moiety and release it for recycling through the salvage pathway. That second role is why intracellular NAD+ concentration is treated as a regulated variable rather than a fixed quantity, and it is the reason the cofactor appears across metabolic, mitochondrial and aging research literature.

NAD+ was first described in 1906, when Arthur Harden and William Young identified a heat stable, dialysable “coferment” in yeast extract that fermentation required. Over the following decades Hans von Euler-Chelpin and Otto Warburg resolved the dinucleotide architecture and the hydride-transfer chemistry that defines the cofactor, work that placed NAD+ among the earliest coenzymes to be chemically characterised.

Peer-reviewed reviews map the current field. Cantó and colleagues reviewed NAD+ metabolism and its relationship to mitochondrial and nuclear energy handling (PubMed 26118927). Verdin surveyed NAD+ in ageing, metabolism and neurodegeneration (PubMed 26785480). Covarrubias and colleagues catalogued cellular processes in which NAD+ availability changes with age (PubMed 33353981). Rajman, Chwalek and Sinclair assessed the in vivo evidence for NAD-raising molecules (PubMed 29514064).

The evidence base is uneven rather than thin. The enzymology is settled: NAD+ dependent reactions have been characterised for close to a century and the identity data in Section 1 are not in dispute. The translational layer remains open. Most in vivo work on raising NAD+ tested precursors rather than NAD+ itself, human studies are limited in size and duration, and no compound in this class has an established outcome profile.

The literature describes NAD+ as an obligate cofactor rather than a receptor ligand. It accepts a hydride at the C4 position of the nicotinamide ring to form NADH, and the ratio between the two forms sets the thermodynamic direction of many dehydrogenase reactions. Sirtuin and PARP activity is reported to track NAD+ availability in the models studied.

One distinction is worth holding: NAD+ is not the same entity as its precursors. Nicotinamide mononucleotide and nicotinamide riboside are salvage-pathway intermediates that cells convert into NAD+, and much of the in vivo literature loosely attributed to NAD+ tested those precursors instead (PubMed 29249689). NAD+ is also distinct from NADP+, a phosphorylated relative supporting reductive biosynthesis and glutathione recycling.

A methodology caveat applies to every concentration figure quoted from this field. Intracellular NAD+ is labile and is compartmentalised between cytosol, nucleus and mitochondria, so measured values depend heavily on extraction chemistry, quench speed and assay platform. Cross-study comparison is only meaningful when the analytical method matches, so consult the methods section of each cited paper.

Lyophilized (freeze-dried) NAD+ is stored at -20°C, shielded from light, and kept sealed until use. Repeated freeze-thaw cycles are avoided. No stability duration is asserted here; the storage and stability data for a given lot are documented on its Certificate of Analysis.

NAD+ is chemically less forgiving than many lyophilized research solids. The glycosidic bond linking nicotinamide to ribose is sensitive to alkaline conditions, and the molecule degrades on warming, so ambient exposure is minimised. Liquid spray products are supplied already in solution and are kept in the closed spray-top bottle under the conditions stated on the label.

Reconstitution means returning a lyophilized compound to solution. This page does not supply a reconstitution procedure. Solvent selection, quantities and technique belong to the methodology of the individual study protocol and to the documentation issued with the lot.

As a general solubility class, NAD+ is a polar, highly water-soluble solid and does not call for an organic co-solvent. Lyophilized material is hygroscopic, meaning it draws moisture from the air, so containers stay closed while equilibrating to room temperature. The lot Certificate of Analysis records appearance and identity for the specific material.

Identity and purity for NAD+ are established from documentation, not inference. Verified purity is documented per lot on the Certificate of Analysis, alongside identity confirmation by chromatographic and mass spectrometric methods. Reconcile the formula and molecular weight in Section 1 against the COA before quantitative work.

House brand material from Novelle Bio and Catalyst Compounds is batch tested with a published Certificate of Analysis. Other brands carry the documentation supplied by their manufacturer. Because NAD+ and NADH behave similarly in some analytical systems, confirm which form a lot of documents.

Compounds researchers commonly study alongside NAD+:

• 5-Amino-1MQ.
  A small-molecule NNMT inhibitor investigated for raising intracellular NAD+ by sparing nicotinamide for the salvage pathway.
• Glutathione.
  The other major cellular redox couple, so GSH/GSSG and NAD+/NADH are frequently assayed together.
• MOTS-c.
  A mitochondrial-derived peptide studied in overlapping metabolic pathways.
• SLU-PP-332 (entry forthcoming).
  A small-molecule ERR agonist investigated in mitochondrial oxidative metabolism.
• Epitalon.
  A short peptide studied in ageing models, often surveyed alongside NAD+.

Cantó C, Menzies KJ, Auwerx J, et al. (2015). NAD+ Metabolism and the Control of Energy Homeostasis: A Balancing Act between Mitochondria and the Nucleus. Cell Metabolism.
PubMed 26118927

Verdin E, et al. (2015). NAD+ in aging, metabolism, and neurodegeneration. Science.
PubMed 26785480

Rajman L, Chwalek K, Sinclair DA, et al. (2018). Therapeutic Potential of NAD-Boosting Molecules: The In Vivo Evidence. Cell Metabolism.
PubMed 29514064

Yoshino J, Baur JA, Imai SI, et al. (2018). NAD+ Intermediates: The Biology and Therapeutic Potential of NMN and NR. Cell Metabolism.
PubMed 29249689

Covarrubias AJ, Perrone R, Grozio A, et al. (2021). NAD+ metabolism and its roles in cellular processes during ageing. Nature Reviews Molecular Cell Biology.
PubMed 33353981

Peptides.com lists seven NAD+ research products across five brands: five lyophilized vials and two liquid sprays supplied in spray-top bottles. Vial specifications run from 250mg to 1000mg per vial, and both sprays are specified at 1500mg per bottle. Every listing is research use only, and each lot is batch tested with a published Certificate of Analysis available through Lab Reports.

• Browse all NAD+ research products
• Catalyst Compounds NAD+, 500mg vial
• Novelle Bio NAD+, 500mg vial
• Verified Peptides NAD+, 1000mg vial
• NuLumin NAD+, 250mg to 500mg vial
• Real Peptides NAD+, 500mg to 1000mg vial
• Catalyst Compounds NAD+ Liquid Spray, 1500mg spray-top bottle
• Novelle Bio NAD+ Liquid Spray, 1500mg spray-top bottle
• Collections: Research Vials and Liquid Sprays. Documentation: COA and Lab Testing.

These products are sold for Research Use Only and are not intended for human consumption.