01 / Reference identity
Identity at a glance.
Public records give these values for NAD+ as the free acid. A supplied lot can be a salt or hydrate with a different formula weight, so its own record governs.
| Type | Dinucleotide cofactor, not a peptide |
|---|---|
| Formula | C21H27N7O14P2 |
| Molecular weight | 663.4 g/mol (free acid) |
| CAS number | 53-84-9 |
| PubChem CID | 5892 |
| Other names | Nadide, coenzyme I |
02 / Molecular architecture
A closer look at the molecule.
Two nucleotide units—one containing adenine and one containing nicotinamide—are joined through a diphosphate connection. The plus sign identifies the oxidized form, NAD+, which is distinct from reduced NADH.
- Adenine nucleotide
- Diphosphate connection
- Nicotinamide nucleotide
Reference information: [1][2][3][4][5]. Actual lot identity must be verified separately.
Two nucleotides rather than amino acids.
NAD+ combines an adenine-containing nucleotide with a nicotinamide-containing nucleotide through a diphosphate connection. That architecture is why an amino-acid sequence diagram would be inappropriate. Its molecular components belong to nucleotide chemistry, even when NAD+ is discussed alongside peptide materials in a catalog.
Redox conversion versus consumption.
NAD+ and NADH form a redox pair. NAD+ can also participate in reactions that consume the molecule, such as those involving PARPs or sirtuins. These are different experimental processes: tracking NADH formation is not automatically a complete account of all NAD+-dependent activity in a sample.
03 / Related forms
NAD+, NADH and NADP+.
The plus sign is a positive charge on the nitrogen of the nicotinamide ring. In NADH, the reduced form, that ring has gained a hydride, a hydrogen with two electrons, and no longer carries the charge. The table sets the two forms side by side.
Both forms absorb ultraviolet light near 260 nm. Only NADH also absorbs near 340 nm (336 nm in Cayman’s record), which is how the two are told apart by absorbance.
NADP+ is a separate molecule: NAD+ with one more phosphate group, on the ribose of its adenosine half.
| NAD+ | NADH | |
|---|---|---|
| Nicotinamide ring | Oxidized, positively charged | Reduced, uncharged |
| Formula | C21H27N7O14P2 | C21H29N7O14P2 |
| Molecular weight | 663.4 g/mol | 665.4 g/mol |
| PubChem CID | 5892 | 439153 |
| Absorbance maxima | 207 and 260 nm | 206, 260 and 336 nm |
04 / Biosynthesis
How cells make NAD+.
A 2021 review by Covarrubias and colleagues describes three routes by which cells make NAD+, each starting from a different small molecule.
| Route | Starting molecule |
|---|---|
| De novo (kynurenine) pathway | Tryptophan, built up from scratch |
| Preiss–Handler pathway | Nicotinic acid |
| Salvage pathway | Nicotinamide, recycled after enzymes consume NAD+ |
This describes cellular biochemistry. It does not describe how any supplied lot was made.
References: [5]
05 / Read the evidence
Research & analytical context.
NAD+ can accept reducing equivalents to form NADH. It also participates in reactions involving enzymes such as sirtuins and PARPs. These roles explain why assays must distinguish redox conversion from NAD-consuming reactions.
Read the references: [1][2][3][4][5].
The distinction that matters
NAD+, NADH and NADP+ are different analytes. A total-NAD measurement is not automatically a measurement of NAD+ alone, and reference free-acid information does not establish a lot’s salt form.
06 / From reference to record
Know the lot, too.
A publication describes its own test material. Your lot’s certificate describes what was tested on that lot. Keep the compound name, batch number and reported methods together when reviewing a result.
Identity & composition
Check sequence or chemical form, terminal modifications, counterion and—where relevant—each blend component.
Analytical results
Read purity, content, sterility and endotoxin results as separate measurements. Only call a test passed when the actual report supports it.
Handling & storage notes
Lyophilized material: Store at −20°C; protect from light and moisture.
Follow the material-specific label and supporting storage documentation. These temperatures do not establish a shelf life.
How to store lyophilized peptides07 / Reference questions
A few details, explained.
What does the + in NAD+ mean?
It is a positive formal charge on the nitrogen of the nicotinamide ring. NAD+ is the oxidized form; NADH, the reduced form, carries an added hydride on that ring and no charge. The sign is chemical notation, not a size, and says nothing about the amount in a vial.
Is total NAD the same measurement as NAD+?
Not necessarily. The assay definition determines which forms are included. A combined measurement should not be reported as a measurement of the oxidized form alone unless the method supports that interpretation.
08 / Continue reading
Go to the source.
Each source is labeled by its type. External sources are not Pioneer batch certificates.
- Cayman Chemical · NAD+ structure and enzyme-cofactor referenceSupplier reference · Read source (opens a new tab)
- PubChem · NAD+ (nadide) identity record, CID 5892Public record · Read source (opens a new tab)
- PubChem · NADH identity record, CID 439153Public record · Read source (opens a new tab)
- Cayman Chemical · NADH reference, with absorbance maximaSupplier reference · Read source (opens a new tab)
- Covarrubias et al. · Review of NAD+ metabolism, including how cells make NAD+ (2021)Published research · Read source (opens a new tab)