Hepps
[CAS 16052-06-5]

Identification

• Classification: Pharmaceutical intermediate >> Heterocyclic compound intermediate >> Piperazine
• Name: Hepps
• Synonyms: 4-(2-Hydroxyethyl)-1-piperazinepropanesulfonic acid; 3-[4-(2-Hydroxyethyl)-1-piperazine]propanesulfonic acid; N-(2-Hydroxyethyl)piperazine-N'-(3-propanesulfonic acid)
• Molecular Formula: C₉H₂₀N₂O₄S
• Molecular Weight: 252.33
• CAS Registry Number: 16052-06-5
• EC Number: 240-198-8
• SMILES: C1CN(CCN1CCCS(=O)(=O)O)CCO

Properties

• Solubility: 100 mM (water)
• Melting point: 237-239 °C

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H302-H315-H319-H335
• Safety Statements: P261-P305+P351+P338

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H302
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	3	H301
Acute toxicity	Acute Tox.	3	H311

Discovery and Applications

HEPPS, or N-(2-hydroxyethyl)piperazine-N'-(3-propanesulfonic acid), is a zwitterionic buffer that belongs to the Good family of buffers. These buffers were developed by Dr. Norman Good and his colleagues in the 1960s to provide a stable pH environment for biochemical and biological research. HEPPS has been specifically synthesized to provide effective buffering in a slightly alkaline pH range, which is critical for many biological and chemical processes.

The molecular formula of HEPPS is C9H20N2O4S. Structurally, it consists of a piperazine ring substituted with hydroxyethyl and propanesulfonic acid groups. This combination gives HEPPS a zwitterionic nature that contributes to its stability and solubility. HEPPS has a pKa of approximately 8.0 at 25°C, making it suitable for buffering in the pH range of 7.5 to 9.0.

HEPPS is widely used as a buffer in a variety of biochemical and molecular biology experiments. Its stability and compatibility with a range of biomolecules make it ideal for maintaining pH in enzymatic reactions, nucleic acid purification, and protein assays. HEPPS is particularly useful in experiments that require a stable, slightly alkaline pH environment.

In electrophoresis, HEPPS is used to prepare buffer solutions that maintain a stable pH during protein and nucleic acid separations. For example, in HEPPS buffer systems, it ensures consistent migration of macromolecules, allowing for accurate analysis and characterization.

HEPPS is used in protein purification protocols such as ion exchange chromatography and affinity chromatography. Its buffering capacity helps maintain the pH of the solution, ensuring that proteins remain in their native functional state during purification. This stability is essential for maintaining protein activity and integrity.

In cell culture applications, HEPPS helps maintain the pH of the culture medium, providing a stable environment for cell growth and function. This stability is critical for sensitive cell lines and primary cultures, which require precise pH control for optimal growth and differentiation.

HEPPS is an important ingredient in diagnostic reagent formulations, especially those that require a stable pH. Its nontoxic nature and compatibility with a variety of biological systems make it suitable for use in diagnostic assays and kits.

References

1951. Der mikrobielle Abbau der Aminosäuren. Archiv für Mikrobiologie, 17, 217-232.
DOI: 10.1007/bf00406733

2024. Investigation of Bottleneck Enzyme Through Flux Balance Analysis to Improve Glycolic Acid Production in Escherichia coli. Journal of Microbiology (Seoul, Korea), 62, 567-575.
DOI: 10.1007/s12275-024-00175-4