NAD+ (nicotinamide adenine dinucleotide) — analytical characterisation
Chromatographic conditions, identity, related substances, presentation, reconstitution and in-use stability.
§6Analytical characterisation
§6.1Chromatographic conditions
- Column
- Ion-pairing reverse phase with a tetrabutylammonium or hexylamine ion-pair reagent, or hydrophilic-interaction chromatography; a conventional C18 method does not retain NAD+
- Mobile phase and gradient
- Ion-pairing: A: 20 mM potassium phosphate pH 6.0 with 5 mM tetrabutylammonium hydrogen sulfate; B: methanol. Gradient 2–30 % B over 15 min
- Detection
- UV 260 nm, where the adenine chromophore absorbs strongly. The 260/340 nm relationship distinguishes NAD+ from NADH, since only the reduced form absorbs at 340 nm — one of the most useful and simplest identity checks available for any compound in this series
- Retention
- Very early on reverse phase without ion pairing; the compound is essentially unretained
§6.2Identity by mass spectrometry
[M+H]⁺ at m/z 664.1; [M−H]⁻ at m/z 662.1, with negative mode generally preferred for nucleotides.[3]
§6.3Related substances and degradation
Table 7. Related substances recorded for NAD+ (nicotinamide adenine dinucleotide), with the process or storage route that generates each and its analytical signature.
| Related substance | Origin | Analytical signature |
|---|---|---|
| NADH (reduced form) | Reduction during processing or storage | +2 Da and a distinctive 340 nm absorbance; a mixture of oxidised and reduced forms is common and the ratio should be stated |
| Nicotinamide | Hydrolysis | A major degradant, readily detected at 260 nm and the endpoint of aqueous degradation |
| Nicotinamide mononucleotide and ADP-ribose | Hydrolysis | Intermediate degradants |
| ADP and AMP | Further hydrolysis | Detected in the same method |
| Endotoxin and bioburden | If intended for parenteral use | Essential for any injectable preparation and not reported in this supply channel |
Degradation routes
- Hydrolysis of the pyrophosphate linkage in aqueous solution, accelerated at neutral and alkaline pH — NAD+ is markedly more stable at acidic pH
- Reduction to NADH
- Alkaline degradation to a fluorescent adduct, which is the basis of a classical assay
- Thermal degradation is rapid; NAD+ solutions should be prepared fresh
§7Presentation, reconstitution and storage
§7.1Presentation and reconstitution
- Presentation
- Lyophilised or crystalline powder; compounded solutions for infusion
- Reconstitution
- A 100 mg vial with 10 mL gives 10 mg/mL. Aqueous NAD+ solutions degrade measurably within hours at room temperature and neutral pH; preparation immediately before use is not a precaution but a requirement.
- Storage, lyophilised
- −20 °C, desiccated, protected from moisture. NAD+ is hygroscopic and moisture uptake drives hydrolysis in the solid state
- Storage, reconstituted
- 2–8 °C and use within hours. The Institute publishes no in-use claim beyond same-day preparation
- In-use period
- Same-day preparation only
NAD+ is the one compound in this series whose degradation can be monitored by a colour change and a simple absorbance ratio, and the Institute notes that the ready availability of a robust identity and purity check makes the absence of such data on supplier certificates harder to excuse than for the peptides.
§7.2In-use stability
Applicable standards: CEI-MS-01 · CEI-MS-02 · CEI-MS-03 · CEI-MS-04 · CEI-MS-05 · CEI-MS-06. The full series is at methodological standards.
Working calculators: reconstitution and insulin-unit conversion · purity against peptide content · certificate minimum-data checker.
References cited on this page
References are numbered in order of first citation in this document. Each superscript in the text links to its entry below.
- United States Pharmacopeial Convention. General Chapter ⟨1225⟩ Validation of Compendial Procedures. United States Pharmacopeia — National Formulary (USP–NF) 2024;USP 2024 Issue 1. identifier not held by the Institute
- International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. ICH Q2(R2) Validation of Analytical Procedures. ICH Harmonised Guideline 2023;Step 4 version, 1 November 2023. identifier not held by the Institute
- International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. ICH Q6B Specifications: Test Procedures and Acceptance Criteria for Biotechnological/Biological Products. ICH Harmonised Tripartite Guideline 1999;Step 4 version. identifier not held by the Institute
- International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. ICH Q1A(R2) Stability Testing of New Drug Substances and Products. ICH Harmonised Tripartite Guideline 2003;Step 4 version. identifier not held by the Institute
- Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharmaceutical Research 2010;27(4):544–575. doi:10.1007/s11095-009-0045-6 · PMID 20143256
Identifiers are reproduced only where the Institute holds them. Where a digital object identifier or PubMed identifier is not shown, the Institute has recorded the journal and year and has not constructed an identifier.