Nicotinic Acid, commonly known as Niacin or Vitamin B3, is a water-soluble vitamin and an established pharmaceutical active ingredient. It is chemically classified as pyridine-3-carboxylic acid and is distinct from nicotinamide, the amide form of vitamin B3.
Nicotinic Acid plays an important biological role as a precursor of the coenzymes NAD and NADP, which are involved in cellular energy metabolism, oxidation-reduction reactions and numerous enzymatic processes.
Nicotinic Acid is used in pharmaceutical and nutritional formulations and is also an important substance for pharmaceutical research, analytical testing and quality-control applications. Pharmacopoeial references identify it as a component of vitamin B formulations.
Nicotinic Acid is a well-established Vitamin B3 pharmaceutical API used in the development and manufacture of pharmaceutical and nutritional formulations.
For pharmaceutical-grade Nicotinic Acid, important quality attributes include:
The European Pharmacopoeia/British Pharmacopoeia monograph provides defined numerical requirements for several of these quality parameters.
Product Name: Nicotinic Acid
Synonyms: Niacin; Vitamin B3; Pyridine-3-carboxylic acid; 3-Pyridinecarboxylic acid
CAS Number: 59-67-6
Molecular Formula: C6H5NO2
Molecular Weight: 123.11 g/mol
IUPAC Name: Pyridine-3-carboxylic acid
Drug / Ingredient Class: Vitamin B3
Therapeutic Class: Vitamin / Nutritional Agent
Therapeutic Area: Nutritional and Metabolic Health
Molecule Type: Synthetic Small Molecule
PubChem confirms the CAS number, molecular formula and molecular weight of Nicotinic Acid.
Nicotinic Acid serves as a precursor for NAD and NADP, coenzymes required for numerous oxidation-reduction reactions and metabolic pathways.
Its biological functions are associated with:
Nicotinic Acid API is relevant to:
Nicotinic Acid is an established source of vitamin B3. Adequate vitamin B3 is required for normal cellular metabolism and physiological function.
At pharmacological doses, nicotinic acid has also been investigated and used in lipid-management applications because of its effects on lipid metabolism. Therapeutic use and dosing should follow the applicable approved product labeling and regulatory requirements.
Nicotinic Acid and Nicotinamide are two chemically distinct forms of Vitamin B3.
Nicotinic Acid:
Nicotinamide:
Therefore, the specifications and molecular data for Nicotinamide should not be transferred to a Nicotinic Acid API page.
Nicotinic Acid is described as a white or almost white crystalline powder. It is sparingly soluble in water, more soluble in boiling water and boiling ethanol, and dissolves in dilute solutions of alkali hydroxides and carbonates.
Pharmacopoeial information describes Nicotinic Acid as:
Solubility can vary according to temperature, solvent concentration and experimental conditions.
The pharmacopoeial identification requirement gives a melting range of:
234–240°C
This is a useful characterization parameter for pharmaceutical-grade Nicotinic Acid.
A controlled Nicotinic Acid API manufacturing process may involve:
The exact commercial manufacturing route should be based on the manufacturer's validated process and applicable regulatory documentation.
Typical Nicotinic Acid API quality-control testing may include:
The pharmacopoeial monograph specifically provides tests for related substances, chlorides, loss on drying, sulfated ash and assay.
The Ph. Eur./BP monograph specifies Nicotinic Acid content of:
99.5%–100.5% on the dried substance.
This is a pharmacopoeial numerical value and is therefore substantially preferable for CMS content to an assumed generic 98–102% API range.
The pharmacopoeial related-substances procedure specifies:
Each unspecified impurity: NMT 0.05%
Total unspecified impurities: NMT 0.05%
Disregard limit: 0.03%
These values are based on the cited Ph. Eur./BP monograph.
The pharmacopoeial specification gives:
Chlorides: NMT 200 ppm
This is an applicable numerical quality-control limit for the referenced Nicotinic Acid monograph.
The pharmacopoeial specification gives:
Loss on Drying: NMT 1.0%
The cited method specifies drying at 105°C for 1 hour.
The pharmacopoeial specification gives:
Sulfated Ash: NMT 0.1%
The cited pharmacopoeial monograph historically specifies:
Heavy Metals: NMT 20 ppm
For a current commercial API specification, however, elemental impurities should be controlled according to the applicable current pharmacopoeial requirements and ICH Q3D, rather than automatically using an obsolete heavy-metals test.
Nicotinic Acid should be stored in a tightly closed container and protected from light under appropriate pharmaceutical storage conditions.
The applicable pharmacopoeial reference specifies protection from light.
Nicotinic Acid is relevant to research involving:
| Parameter | Specification |
|---|---|
| Appearance | White crystalline powder or crystals |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 99.5% – 100.5% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.1% |
| Individual Impurity | NMT 0.05% |
| Total Impurities | NMT 0.05% |
| Water Content | NMT 1.0% |
| Melting Point | 234–240°C |