Synonym(s): 2-(N-Morpholino)ethanesulfonic acid, 4-Morpholineethanesulfonic acid

Description

In biological experiments, it is an important pH stabilizing reagent. Usually, an appropriate weak acid is mixed with its conjugate base to obtain a suitable pH value.
Most biological reactions occur under neutral conditions, and the pH is generally selected between 6-8. Meanwhile, the effective buffering range of the buffer is required to be between 6-8 as well.

In addition, it is required that the acidic and basic forms of the buffer do not undergo chelation with certain metal ions.

Specifications

Item	Value
Chemical Name	2-Morpholinoethanesulfonic Acid
Appearance	Pure white Powder
CAS No.	4432-31-9
Molecular Formula	C6H13NO4S
Molecular Weight	195.2
Grade	Biochemical Grade
Purity	≥99.0%
PKa at 20℃	6.05-6.25
Color Degree (1M reagent solution)	Transparent
Heavy Metals	≤10PPM
Sulfates	≤100PPM
Iron	≤10PPM
Chlorides	≤100PPM
Storage / Handling	Store at Room Temperature.

Features

High purity, biochemical-grade quality: ≥ 99.0% purity ensures minimal contaminants (heavy metals ≤ 10 ppm, sulfates/chlorides ≤ 100 ppm; iron ≤ 10 ppm), suitable for sensitive biological and biochemical applications.
Accurate buffering around physiological pH: The compound has a pKₐ ≈ 6.15–6.25 (at ~20–25 °C) and buffers effectively in the pH range ~5.5–7.0 (often used pH 6.0–6.5), matching many biological reaction and culture requirements.
Excellent water solubility: Readily dissolves in deionized/distilled water to yield clear, transparent solutions — convenient for preparing buffers at various concentrations.
Minimal UV absorption / low interference: As a “Good’s buffer,” MES exhibits minimal absorption in UV/visible range, making it compatible with UV-sensitive assays and spectrophotometric measurements.
Non-coordinating / minimal metal binding: Unlike phosphate- or acetate-based buffers, MES does not strongly chelate common divalent metal ions (Ca²⁺, Mg²⁺, Mn²⁺, Cu²⁺), reducing risk of interference in metal-dependent assays or protein purification workflows.
Chemically and enzymatically stable: MES is stable under typical laboratory conditions, both chemically and biologically, minimizing buffer degradation or side-reactions.

Applications

Buffer solutions for biochemical and molecular biology experiments: Suitable for preparing buffer solutions for protein/enzyme assays, nucleic acid procedures (e.g., DNA/RNA purification), and general biochemical reactions requiring stable pH.
Cell culture media (bacterial, yeast, mammalian, plant): Especially useful when a stable slightly acidic to near-neutral pH (≈ 5.5–7.0) is needed; as a zwitterionic buffer, MES is not readily absorbed by cell membranes, reducing cytotoxicity or interference.
Protein purification & chromatography workflows: Works well for protein purification (e.g., ion-exchange chromatography), buffer exchange/dialysis, antibody or peptide handling during binding/elution steps.
Electrophoresis buffers & gel systems: Useful as a running buffer for gel electrophoresis (e.g., PAGE), especially when low UV absorbance and stable pH are required.
Stabilization of enzymes, proteins, and other biomolecules: Buffering near pH 6.0 helps maintain proper protein charge states, activity, and stability — beneficial for enzymatic reactions, storage buffers, and biochemical assays.

Safety Disclaimer

This product is intended for laboratory research use only. Not for drug, human, or veterinary use. Review the Safety Data Sheet (SDS) provided by BioFargo for detailed handling, storage, hazard, and disposal information. Use appropriate personal protective equipment (PPE) including gloves, lab coat, and eye protection when handling. Dispose of waste and residual buffer in accordance with local, state, and federal regulations. Ensure proper ventilation if preparing large volumes or heating solutions.

Documents

MSDS

MES 99% Biochemical Grade