N-(Hydroxyethyl)piperazine-N'-2-hydroxypropanesulfonic acid
[CAS# 68399-78-0]

Identification

• Classification: Chemical reagent >> Organic reagent >> Sulfonic acid / sulfinic acid
• Name: N-(Hydroxyethyl)piperazine-N'-2-hydroxypropanesulfonic acid
• Synonyms: HEPPSO
• Molecular Formula: C₉H₂₀N₂O₅S
• Molecular Weight: 268.33
• CAS Registry Number: 68399-78-0
• EC Number: 269-990-1
• SMILES: C1CN(CCN1CCO)CC(CS(=O)(=O)O)O

Properties

• Solubility: 100 mM (water)

Safety Data

• Hazard Symbols: GHS06;GHS07 Danger
• Risk Statements: H301-H315-H319-H335
• Safety Statements: P261-P264-P264+P265-P270-P271-P280-P301+P316-P302+P352-P304+P340-P305+P351+P338-P319-P321-P330-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

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

Discovery and Applications

N-(Hydroxyethyl)piperazine-N'-2-hydroxypropanesulfonic acid, commonly known as HEPPSO, is a zwitterionic buffer. Its development stemmed from the need for a stable and reliable buffer in biochemical and biological research. It was discovered during an ongoing effort to expand the library of Good buffers, named after Norman E. Good, who first proposed a set of criteria for an ideal biological buffer in the 1960s. These criteria emphasized minimal interference with biological systems, chemical stability, and nontoxicity.

The molecular formula of HEPPSO is C9H20N2O6S, and its molecular weight is 284.33 g/mol. The molecule consists of a piperazine ring substituted with hydroxyethyl and hydroxypropanesulfonic acid groups. This structure gives HEPPSO excellent buffering capacity. It is effective over a pH range of 7.2 to 8.5, with a pKa value of approximately 7.8 at 25°C. These properties make HEPPSO suitable for maintaining near-neutral to slightly alkaline pH conditions, which are essential in many biological applications.

HEPPSO is widely used in electrophoresis buffers, especially for protein and nucleic acid separations. Its stable buffering capacity ensures that the pH remains consistent throughout the electrophoresis process, which is essential for accurate separation and resolution of biomolecules. HEPPSO's compatibility with various electrophoresis techniques enhances its usefulness in research.

In cell culture applications, HEPPSO helps maintain the pH of the culture medium within the physiological range, promoting optimal cell growth and viability. Its non-toxic properties ensure that it does not interfere with cellular processes, making it a reliable buffer for maintaining consistent experimental conditions in cell studies.

HEPPSO is used in various biochemical assays to stabilize pH, which is essential for the activity and stability of enzymes and other biomolecules. Its ability to maintain a stable pH environment ensures accurate and reliable assay results, making it an important component of enzyme research and other biochemical analyses.

During protein purification, maintaining a stable pH is essential to preserve protein structure and function. HEPPSO is used in chromatographic techniques and other purification protocols to buffer the system, improving the yield and purity of isolated proteins. Its compatibility with different purification methods makes it a versatile tool in protein chemistry.

In structural biology, HEPPSO is used in techniques such as X-ray crystallography and NMR spectroscopy to study the structure of proteins and other biomolecules. Its stability and low ionic strength make it an ideal buffer for obtaining high-quality structural data without interfering with the biomolecule being analyzed.

The high buffering capacity allows HEPPSO to effectively maintain a stable pH, ensuring consistent experimental results. HEPPSO has a wide pH range and can be used in a variety of experimental conditions, making it a versatile buffer. HEPPSO is generally nontoxic to cells and does not interfere with biochemical reactions, making it suitable for sensitive biological applications.

References

1998. Buffers for the Physiological pH Rangeä Thermodynamics of the Second Dissociation of N-(2-Hydroxyethyl)piperazine-N'-2-hydroxypropanesulfonic Acid From 5 to 55°C. Journal of Solution Chemistry, 27(5).
DOI: 10.1023/aä1022600604950

2002. Complexation of Copper by Zwitterionic Aminosulfonic (Good) Buffers. Analytical Chemistry, 74(24).
DOI: 10.1021/ac0261101

1995. Effects of organic pH buffers on a cell growth and an antibody production of human-human hybridoma HB4C5 cells in a serum-free culture. Cytotechnology, 17(1).
DOI: 10.1007/bf00749399