Quick answer
NAD+ is a 663 Da dinucleotide (C21H27N7O14P2), so verification means HPLC purity plus mass-based identity on a lot-specific COA, and attention to heat and moisture.
- Identity: intact dinucleotide, confirmed by mass, not just a UV peak
- Purity: HPLC with the method named and degradants resolved
- Stability: heat and alkaline pH hydrolyze NAD+; store 2–8 °C, −20 °C long-term
- V8 listing: 1000 mg lyophilized; see the product page and COA page
- Research use: For laboratory research use only; not for human consumption.
For laboratory research use only; not for human consumption.
NAD+ (nicotinamide adenine dinucleotide) is a defined small molecule, a dinucleotide of about 663 Da with the formula C21H27N7O14P2, rather than a synthesized peptide chain. Evaluating a supplier therefore uses a slightly different set of questions than for the rest of this catalog, but the principle is the same: do not take a vial's contents on faith. NAD+'s growing presence in metabolic and aging-adjacent research has also brought a wider range of sellers into the market, which makes documentation-first evaluation more useful than it was when the coenzyme was a niche biochemistry reagent. This guide covers what to verify, why NAD+ is chemically sensitive, and how the V8 listing fits. For the biology, see the NAD+ research overview.
What "verified" should mean for NAD+
A credible supplier documents purity with a real, method-attributed number, typically HPLC-based, rather than a bare percentage on a label. See HPLC purity analysis for what that number represents and how it is generated.
Identity, not just purity
Purity alone does not confirm you are holding NAD+ rather than a related nucleotide or a degradation product. NADH, NADP+, nicotinamide mononucleotide (NMN), ADP-ribose and AMP all absorb light near 260 nm because of the adenine ring, so a UV-based chromatogram can look similar for several of them. Look for documentation that includes mass-based identity confirmation (the intact molecule appears at roughly m/z 664 as the protonated ion) alongside chromatography. See HPLC vs. mass spectrometry.
Batch-specific documentation
A certificate of analysis tied to the exact lot in your vial is worth far more than a generic specification sheet reused across every batch. See how to read a COA for what a legitimate one includes.
Independent confirmation
Where a supplier offers third-party test results alongside its own internal data, that is a meaningful signal that the purity claim is not just marketing copy. Background: third-party testing explained.
Handling that matches the chemistry
NAD+ is more chemically sensitive in solution than many research compounds, so honest reconstitution and storage guidance, not generic boilerplate, is itself a marker of a supplier that understands what it is selling.
Why NAD+ needs different scrutiny from a peptide
| Aspect | Typical synthetic peptide | NAD+ |
|---|---|---|
| Structure | Amino-acid chain with a sequence | Dinucleotide: nicotinamide riboside + ADP linked by a pyrophosphate |
| Main impurities | Truncations, deletions, oxidation | NADH, nicotinamide, ADP-ribose, AMP, NMN, salts |
| Identity proof | Mass vs. sequence | Mass plus retention time against a reference; formula C21H27N7O14P2 |
| Main stability risk | Aggregation, oxidation | Hydrolysis of the nicotinamide-ribose bond, especially with heat or alkaline pH |
| Water content | Moderate | Hygroscopic; moisture uptake affects weighed amount |
In practice this means the headline HPLC percentage matters less than whether the report identifies and separates the likely degradation products. Nicotinamide, the main hydrolysis product, is visible in a well-designed reversed-phase or ion-pairing method; a poorly resolved method can hide it. For the compound-specific testing approach, see NAD+ purity testing.
Common related species and how they arise
| Species | Relationship to NAD+ | Why it appears in a lot |
|---|---|---|
| NADH | Reduced form of the same coenzyme | Incomplete oxidation during manufacture or a process by-product |
| Nicotinamide | Released when the nicotinamide-ribose bond is cleaved | Hydrolysis from heat, moisture or alkaline conditions |
| ADP-ribose | Remainder after nicotinamide loss | Same hydrolysis, or contaminating NAD+-consuming enzyme activity in biological preparations |
| NMN, AMP, ADP | Fragments and precursors on the NAD+ biosynthesis path | Starting materials or breakdown at the pyrophosphate linkage |
| Inorganic salts and water | Not NAD+-related | Counter-ions and hygroscopic moisture; lower the effective NAD+ content of the powder |
This list is the reason a documentation-first buyer asks which of these species the method can separate. If a report shows a single peak but the method cannot resolve nicotinamide or NADH from NAD+, the percentage says little about degradation. The absorbance spectrum is also informative: NAD+ has a single maximum near 260 nm, whereas NADH adds a second band near 340 nm, so a diode-array trace showing 340 nm absorbance in the main peak suggests reduced contamination. Ask suppliers whether the retention time was confirmed against a reference standard, since a nucleotide with a similar spectrum could otherwise occupy the same window.
Shipping conditions
Because heat accelerates hydrolysis of the intact dinucleotide, how a supplier ships lyophilized NAD+ is worth checking before ordering. Packaging that accounts for transit time and seasonal temperature swings, rather than a one-size-fits-all method, reduces the chance that a vial arrives partly degraded. Ask what the packaging is, how long a typical transit takes and what the supplier does if a package is delayed. General practice is covered in how research peptides are shipped. On arrival, refrigerate the vial promptly; V8 specifies storage at 2–8 °C, with −20 °C for long-term storage, protected from heat, moisture and light.
What to look for on the label
- Defined identity: the intact dinucleotide, molecular formula C21H27N7O14P2, not an ambiguous "NAD" blend or a precursor like NMN or nicotinamide riboside sold under a similar name. For how they differ, see NAD+ vs. NMN vs. NR.
- Measured purity with the analytical method named.
- Lot-specific COA shipped with, or available for, the exact vial received.
- Clear research-use-only labeling, with no suggestion of human or animal use.
- Stated quantity per vial and how it was determined.
Choosing a vial size
Vial size is a practical decision for research planning rather than a quality signal. The V8 listing is a single 1000 mg size, and the trade-offs between larger and smaller vials, including how much material can reasonably be used before reconstituted solution degrades, are discussed in NAD+ 500 mg vs. 1000 mg vial size. A useful rule: size the vial to what a lab will consume within the validated stability window of the working solution, then store the rest lyophilized. Stock concentration is mass divided by volume (mg/mL); for a 1000 mg vial in 20 mL of diluent that is 50 mg/mL, and the calculator handles other volumes. Confirm solubility and solution pH for your own buffer before preparing a large stock, since NAD+ solutions are acidic and sensitive to alkaline conditions.
Questions to ask before you order
- Is the purity figure from HPLC, and can I see the chromatogram and method?
- Was identity confirmed by mass spectrometry?
- Does the COA lot number match the vial that will ship?
- Is there independent testing in addition to in-house data?
- What are the recommended storage conditions, and how is the product packed for transit?
Broader checklists: choosing a supplier, vetting a research supplier and red flags when buying.
Where V8 Peptides fits
V8 Peptides lists NAD+ as a lyophilized powder, 1000 mg, with ≥98% purity stated on the page, in a sealed glass research vial. The listing describes batch-specific analytical documentation (lot number, test date, measured HPLC purity, molecular-identity confirmation) and storage guidance, and orders ship via USPS. Batch records are organized on the COA page, and the product page currently shows its COA status as in progress, so check the state of the lot you want. The listing is here: NAD+ research vials. For application context, see NAD+ research applications.
Frequently asked questions
Is NAD+ a peptide?
No. It is a dinucleotide coenzyme, C21H27N7O14P2, about 663 Da. It is sold alongside peptides, but its verification relies on HPLC and mass identity against a small-molecule reference rather than an amino-acid sequence.
Why is HPLC purity alone not enough for NAD+?
Related nucleotides such as NADH, NMN and ADP-ribose also absorb near 260 nm. Mass-based identity confirmation and a method that resolves nicotinamide and other degradants are needed.
What degrades NAD+?
Mainly hydrolysis of the nicotinamide-ribose bond, which is accelerated by heat and alkaline pH, plus moisture uptake in the hygroscopic powder. That is why storage and transit conditions matter.
How should lyophilized NAD+ be stored?
V8 specifies refrigeration at 2–8 °C, freezing at −20 °C for long-term storage, and protection from heat, moisture and light.
What vial size does V8 list?
A single 1000 mg lyophilized vial, per the product page, with ≥98% purity stated.
How do I work out stock concentration?
Concentration in mg/mL equals vial mass divided by diluent volume, so 1000 mg in 20 mL is 50 mg/mL. Check solubility in your buffer first; the calculator does the arithmetic.
How is NAD+ different from NMN or nicotinamide riboside?
NMN and NR are precursors that cells convert to NAD+; NAD+ is the finished coenzyme. They have different masses and are separate compounds, as covered in NAD+ vs. NMN vs. NR.
Where can I see batch documentation?
On the COA page. The NAD+ product page shows the current COA status, so confirm it for the lot you intend to order.
Research Use Only. For laboratory research use only; not for human consumption. Supplied strictly for laboratory research and development, not for human or veterinary use, and not for any diagnostic or clinical purpose. This article is research education, not usage guidance.