NAD+ — wholesale 10-vial kits

Research context

β-Nicotinamide adenine dinucleotide, NAD+, is a coenzyme rather than a peptide, and it is stocked here alongside the peptide catalog because it is a routine reagent in the same metabolic and mitochondrial research. Structurally it is a dinucleotide: a nicotinamide ribonucleotide and an adenine ribonucleotide linked through a pyrophosphate bridge. NAD+ is the oxidized form; accepting a hydride at the nicotinamide ring gives the reduced form, NADH. That reversible interconversion between NAD+ and NADH is the basis of its first role, as the electron-carrying cofactor for the oxidoreductases of central metabolism.

In the laboratory the oxidized/reduced pair is the foundation of dehydrogenase enzyme assays. Because NADH absorbs strongly at 340 nm and NAD+ does not, the appearance or disappearance of NADH gives a direct spectrophotometric readout of enzyme activity, and coupled assays built on that signal are used to follow a very wide range of reactions. Supplying NAD+ as a defined reference reagent is what lets those assays be quantified against a known cofactor concentration, and the NAD+/NADH ratio itself is a commonly measured index of a sample's metabolic and redox state.

The second role is as a consumed substrate for non-redox, NAD+-dependent enzymes, and this is where most current interest sits. The sirtuins are NAD+-dependent protein deacetylases: the 2000 Nature report from Imai, Armstrong, Kaeberlein and Guarente that yeast and mouse Sir2 are NAD-dependent histone deacetylases is the work that connected the coenzyme to chromatin and to the biology of aging. The poly(ADP-ribose) polymerases, PARPs, consume NAD+ to build ADP-ribose polymers in DNA-damage signaling, and the ectoenzyme CD38 degrades it. Each of these makes NAD+ a required substrate in its in-vitro assay, so defined NAD+ is used both as the cofactor and as the thing whose consumption is measured.

Those two roles converge on mitochondrial and metabolic research. Reviews by Cantó, Menzies and Auwerx in 2015 and by Covarrubias and colleagues with Verdin in 2021 describe how NAD+ availability couples cellular energy status to sirtuin activity, mitochondrial function and the broader set of pathways the coenzyme touches, and a 2015 Science overview by Verdin set out its place in metabolism and neurodegeneration. For a bench scientist this means NAD+ turns up in assays of mitochondrial dehydrogenases, in sirtuin and PARP activity measurements, and in extracts where the NAD+/NADH ratio is read out — settings for which accurate quantification of the coenzyme is essential. Yoshino and Imai's 2013 reverse-phase HPLC method for measuring NAD+ in cells and tissues is a standard reference for that quantification.

This item is supplied as 500 mg of lyophilized NAD+ per vial. Regulatory position, stated factually: NAD+ is an endogenous coenzyme and a standard biochemical reagent; the material sold here is a research reference standard and is not offered as, or as a component of, any approved product. WholesalePeptide.us supplies it for laboratory research only.

Practical note for assay design: NAD+ is hygroscopic and hydrolyzes slowly in aqueous solution, faster under alkaline conditions and warmth, so stocks are made fresh, kept cold, and often held slightly acidic. Because it is not a peptide, its identity is confirmed on each lot COA by mass and purity against the dinucleotide structure, and net content governs how much cofactor is actually delivered into an assay.

Research areas

• sirtuin (NAD+-dependent deacetylase) activity assays
• PARP and ADP-ribosylation assays
• dehydrogenase enzyme assays (NADH absorbance at 340 nm)
• NAD+/NADH ratio measurement in cell and tissue extracts
• mitochondrial and metabolic research
• analytical reference standard for NAD+ quantification by HPLC

Handling and storage

• Store lyophilized vials at −20 °C, sealed, protected from light and moisture.
• Let the vial equilibrate to room temperature before opening to limit condensation.
• Reconstitute in an appropriate sterile buffer or solvent according to your laboratory SOP.
• NAD+ is hygroscopic and hydrolyzes in aqueous solution, faster when warm or alkaline; prepare stocks fresh, keep them cold, and minimize freeze–thaw.