• USA Home
  • RES6008H-A7 - HEPES, Hemisodium Salt


HEPES, Hemisodium Salt

PharmaGrade, Manufactured under appropriate controls for use as a raw material in pharma or biopharmaceutical production, suitable for cell culture

Synonym: 4-(2-Hydroxyethyl)piperazine-1-ethanesulfonic acid hemisodium salt, N-(2-Hydroxyethyl)piperazine-N′-(2-ethanesulfonic acid) hemisodium salt, HEPES hemisodium salt

  • CAS Number 103404-87-1

  • Empirical Formula (Hill Notation) C8H17.5N2O4S · 0.5Na

  • Molecular Weight 249.30

  •  NACRES NA.21



Related Categories Biochemicals and Reagents, Biological Buffers, Good’s Buffers, PharmaGrade Buffers
Quality Level   400
biological source   synthetic
Agency/Method   non-compendial
product line   PharmaGrade
assay   ≥96.0% NaOH basis (Reverse titration)
form   powder
application(s)   cell culture | mammalian: suitable
impurities   Endotoxin and microbial; tested
useful pH range   6.8 - 8.2
pKa    7.5
suitability   suitable for manufacturing use
foreign activity   Cytotoxicity, DNase, NICKase, RNase, and Protease; tested
SMILES string   [Na+].OCCN1CCN(CC1)CCS([O-])(=O)=O


General description

PharmaGrade products are manufactured under appropriate controls for use as a raw material in pharma or biopharmaceutical production. For more information on the PharmaGrade Program, visit sigma-aldrich.com/safc-pharmagrade.


HEPES Hemisodium is a biological buffer often referred to as a “Good’s” buffer. As the hemisodium salt, this buffer can be used directly to prepare a working buffer solution of HEPES. This biological buffer formulation is ideal since the pKa of the buffer is 7.31 which corresponds to the physiological pH of 7.36. HEPES Hemisodium is considered to be non-toxic to culture cell lines, highly water soluble and provides high-solution clarity.

HEPES Hemisodium can be used in cell culture media, biopharmaceutical buffer formulations (both upstream and downstream) and diagnostic reagent formulations.


Product is available in the following package sizes:
RES6008H-A701X: 100 gm container
RES6008H-A702X: 1 kg container
RES6008H-A704X: 10 kg container


Enhanced Quality Product Documentation on PharmaGrade HEPES, Hemisodium Salt

Safety & Documentation

Safety Information

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

pHast Pack
Protocols & Articles

Related Content

BioUltra Biological Buffers

A buffer, as defined by Van Slyke [1], is "a substance which by its presence in solution increases the amount of acid or alkali that must be added to cause unit change in pH". Buffers are thus very i...
Keywords: Absorption, Adsorption, Biochemistry, Biological Buffers, Biological processes, Buffers, PAGE

Enhanced Quality Program [VIDEO]

The Enhanced Quality Program is a quality management system that is used to differentiate products based on the required level of transparency, control and documentation support determined by the nee...

One Quality Policy [VIDEO]

Sigma-Aldrich maintains one quality policy on a global level to provide consistency in vision, maintained across all manufacturing and distribution sites so that the company on the whole is adhering ...

Quality Management Systems [VIDEO]

See how we combine the use of various Quality Management Systems to manage manufacturing and supply chain for our products, as well as ensure data integrity for information provided to customers via ...

Risk Management [VIDEO]

Our Quality Policy means that we are able to provide certain information to end customers based on a product’s Enhanced Quality level, and that information is limited to what we are able to guarantee...

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?