NAD+

1 Identity

Endogenous pyridine dinucleotide coenzyme - not A peptide and not peptide-adjacent. It is carried in this catalog only because the peptide market sells it; it shares none of the manufacturing, immunogenicity or receptor-pharmacology characteristics of peptides, and it is released against a small-molecule panel accordingly.

Sequence

No sequence - not a peptide, and no peptide bond exists anywhere in the structure. The molecule is a dinucleotide: nicotinamide riboside and adenosine joined through a pyrophosphate bridge. It carries a quaternary pyridinium nitrogen, which is what the '+' in the name denotes; because that permanent cation is balanced internally by a deprotonated pyrophosphate oxygen, the species written as NAD+ is a ZWITTERION and its correct neutral molecular formula carries no net charge. Four stereocenters on each ribose, eight in total, all fixed by the biosynthetic or enzymatic route; the anomeric configuration at the nicotinamide ribose is the beta form, and the alpha anomer is a real and separately sold impurity that is exactly isobaric.

Molecular formula

C21H27N7O14P2 (free acid, zwitterionic inner salt; PubChem CID 5892). Disodium salt C21H25N7Na2O14P2. Hydrates are common and are declared per lot; the hydrate water is part of the label claim arithmetic and not an impurity.

Average mass

663.430 Da for the free acid, from C21H27N7O14P2 on IUPAC 2021 abridged conventional atomic weights (C 12.011, H 1.008, N 14.007, O 15.999, P 30.973761998). The figure of approximately 663.43 that circulates in supplier catalogs is consistent with it. Disodium salt 707.393 Da (C21H25N7Na2O14P2). Monosodium salt 685.411 Da. A common presentational error to guard against: writing NAD+ as a cation C21H28N7O14P2+ inflates the stated mass by about 1.008 Da and is not the convention any major catalog uses.

Monoisotopic mass

663.1091 Da neutral monoisotopic for the free acid, C21H27N7O14P2. [M+H]+ 664.1164; [M-H]- 662.1018; [M+2H]2+ 332.5618. Disodium salt 707.0730 neutral monoisotopic. The two deltas that matter analytically: NADH is exactly +2.0157 monoisotopic above NAD+ (C21H29N7O14P2, 665.1248), and NADP+ is exactly +79.9663 above it (C21H28N7O17P3, 743.0755).

Salt / variant note

Five separately sold molecules and two salt axes move through this shelf, and the price gap between them is large enough to make substitution economic. (1) NADH, the reduced form, C21H29N7O14P2, avg 665.446 / mono 665.1248 - exactly +2.0157 monoisotopic, which is well inside the error of a nominal-mass reading and is the single likeliest wrong article to pass a loose identity test. (2) NADP+, C21H28N7O17P3, avg 743.408 / mono 743.0755, +79.9663 (one HPO3). (3) NADPH, C21H30N7O17P3, avg 745.424 / mono 745.0911. (4) beta-Nicotinamide mononucleotide (NMN), C11H15N2O8P, avg 334.221 / mono 334.0566 - half the molecule and a separate catalog article; NMN has its own record here, and its status as a dietary-supplement ingredient is contested, with no primary FDA source establishing it. (5) Nicotinamide riboside, usually supplied as the chloride, C11H15ClN2O5, avg 290.700 / mono 290.0670. (6) Nicotinamide itself, C6H6N2O, avg 122.127 / mono 122.0480 - the cheapest article on the shelf by a wide margin and the hydrolysis product of the others. Salt and hydrate are the two further axes and neither is an impurity: disodium salt C21H25N7Na2O14P2 avg 707.393, monosodium avg 685.411, with hydrates of both in commerce, so gross weight does not equal NAD+ weight until the salt and the water are both declared and quantified. Finally, and least visible: the alpha-NAD anomer, which shares the formula C21H27N7O14P2 and therefore both masses exactly, is separately cataloged by institutional suppliers, and cannot be excluded by mass at any resolving power - only by chromatography against a characterized standard, or by optical rotation.

2 Class & testing panel

Form

Single article

Testing panel

P6 — panel definition

3 Primary sources & evidence

The index reports the design and provenance of the literature, not a conclusion about effect.

Human randomized trial comparing three NAD-related interventions: Christen S et al., Nature Metabolism 2026, PMID 41540253. Registered studies: NCT06882096, Phase 1, n=32, recruiting, tracing metabolic flux of orally administered precursors in healthy adults; NCT06776510, Phase 1/2, n=20, recruiting, in immune thrombocytopenia. Neighboring precursor literature, which belongs to different molecules and is badged as such: Pencina KM et al., J Gerontol A Biol Sci Med Sci 2023, PMID 35182418; Yoshino M et al., Science 2021, PMID 33888596; Yi L et al., Geroscience 2023, PMID 36482258; Kim M et al., Nutrients 2022, PMID 35215405; Morifuji M et al., Geroscience 2024, PMID 38789831. Research applications recorded for the reagent itself: isotope-tracer studies of NAD metabolism and compartmentalization, substrate for sirtuin, PARP and CD38 enzymology in vitro, and NAD/NADH redox-ratio measurement in cell and tissue models. Long-term human safety data for repeated intravenous exposure: none identified.

4 Storage & specification

Storage

Hygroscopic white to off-white or faintly yellow solid. Store desiccated at -20 degrees C, protected from light, in the sealed original container; equilibrate to room temperature before opening to prevent condensation onto the solid. The article is unstable in aqueous solution, particularly at alkaline pH and at elevated temperature, so solutions are prepared fresh for assay use and are not stockpiled; the label states this and the certificate repeats it. Compound-specific stability limits are taken from the supplier's certificate rather than assumed. Ships with a labeled cumulative excursion allowance and a single-use temperature logger in every export carton.

Shelf life

Provisional 24-month retest interval for the lyophilized or crystalline solid at -20 degrees C, desiccated and light-protected, stated as provisional pending this company's own stability data. No shelf life at all is assigned to solutions: aqueous instability at alkaline pH and elevated temperature is a documented property of this molecule, so solutions are prepared fresh and are not held. The confirming study is an ICH Q1A(R2) design with free nicotinamide, NADH content and water as the stability-indicating attributes at 0, 3, 6, 9, 12, 18 and 24 months at -20 degrees C, with 2 to 8 degrees C and 25 degrees C / 60 percent RH arms. Printed retest date on every vial, first-expiry-first-out enforced against it.