PHR1416 Supelco

Sodium Citrate

Pharmaceutical Secondary Standard; Certified Reference Material

Synonym: Citric acid trisodium salt dihydrate, Sodium citrate tribasic dihydrate, Trisodium citrate dihydrate

  • CAS Number 6132-04-3

  • Linear Formula HOC(COONa)(CH2COONa)2 · 2H2O

  • Molecular Weight 294.10

  •  Beilstein/REAXYS Number 6104939

  •  EC Number 200-675-3

  •  MDL number MFCD00150031

  •  PubChem Substance ID 329823386

  •  NACRES NA.24



Related Categories Analytical Standards, Analytical/Chromatography, Chinese Food Contact Materials Regulation GB 9685 2016, Food & Beverage Standards, Food Contact Materials,
Quality Level   300
grade   certified reference material
  pharmaceutical secondary standard
form   neat
application(s)   HPLC: suitable
  gas chromatography (GC): suitable
mp   >300 °C (lit.)
Featured Industry   Pharmaceutical (small molecule)
format   neat
pharmacopeia traceability   traceable to USP 1613859
SMILES string   O.O.[Na+].[Na+].[Na+].OC(CC([O-])=O)(CC([O-])=O)C([O-])=O
InChI   1S/C6H8O7.3Na.2H2O/c7-3(8)1-6(13,5(11)12)2-4(9)10;;;;;/h13H,1-2H2,(H,7,8)(H,9,10)(H,11,12);;;;2*1H2/q;3*+1;;/p-3


General description

Sodium citrate, also known as E331, is a tri-sodium salt of citric acid. In food products, it is commonly used as a flavor and preservative. In pharmaceutical formulations, it is used as a buffer, emulsifier and sequestering agent.
Pharmaceutical secondary standards for application in quality control, provide pharma laboratories and manufacturers with a convenient and cost-effective alternative to the preparation of in-house working standards.


Sodium citrate may be used as a pharmaceutical reference standard for the determination of the analyte in raw material, food and pharmaceutical formulations by titrimetry.

These Secondary Standards are qualified as Certified Reference Materials. These are suitable for use in several analytical applications including but not limited to pharma release testing, pharma method development for qualitative and quantitative analyses, food and beverage quality control testing, and other calibration requirements.

Analysis Note

These secondary standards offer multi-traceability to the USP, EP and BP primary standards, where they are available.

Other Notes

This Certified Reference Material (CRM) is produced and certified in accordance with ISO 17034 and ISO/IEC 17025. All information regarding the use of this CRM can be found on the certificate of analysis.


To see an example of a Certificate of Analysis for this material enter LRAC3037 in the slot below. This is an example certificate only and may not be the lot that you receive.

Safety & Documentation

Safety Information

NONH for all modes of transport
WGK Germany 
Flash Point(F) 
Not applicable
Flash Point(C) 
Not applicable


Certificate of Analysis (COA)

Please Enter a Lot Number
Protocols & Articles
Peer-Reviewed Papers


Related Products

Technical Service:

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Bulk Ordering & Pricing:

Need larger quantities for your development, manufacturing or research applications?