ISETHIONATE

Isethionate is commonly used in the personal care and cosmetics industry as a mild surfactant and cleansing agent.
Isethionate is especially valued in shampoos, facial cleansers, and body washes because it cleans effectively without stripping the skin of its natural oils.

Isethionate (focusing on the commonly used form, sodium isethionate):
CAS Number: 1562‑00‑1
EC / EINECS Number: 216‑343‑6
Molecular Formula: C₂H₅NaO₄S
Molecular Weight: 148.11 g/mol

Isethionate (the corresponding information for the free acid form, Isethionic Acid):
CAS Number: 107‑36‑8
EC / EINECS Number: 203‑493‑0
Molecular Formula: C₂H₆O₄S
Molecular Weight: 126.13 g/mol

SYNONYMS:
Isethionate, CHEBI:61904, RefChem:1087497, 2-Hydroxyethanesulfonate, 2-hydroxyethane-1-sulfonate, Isethionate(1-), 2-Hydroxyethanesulfonate(1-), SUMDYPCJJOFFON-UHFFFAOYSA-M, NCGC00248569-01, Q27131488

Isethionic Acid Synonyms: 
2‑Hydroxyethanesulfonic acid, 2‑hydroxyethylsulfonic acid, beta‑hydroxyethanesulfonic acid, ethanolsulfonic acid, isethionate (free acid).

Sodium Isethionate Synonyms: 
Sodium isethionate, isethionic acid sodium salt, sodium 2‑hydroxyethanesulfonate, ethane‑1‑sulfonate 2‑hydroxy‑ sodium salt, sodium beta‑hydroxyethanesulfonate, sodium hydroxyethylsulfonate, ethane‑sulfonic acid 2‑hydroxy‑ monosodium salt, 2-Hydroxyethanesulfonic Acid Sodium Salt, Isethionic Acid Sodium Salt, Sodium 2-Hydroxyethanesulfonate,

Isethionates are esters of long-chain aliphatic carboxylic acids (C8 – C18) with isethionic acid (2-hydroxyethanesulfonic acid) or salts thereof, such as ammonium isethionate or sodium isethionate.
Isethionates are also referred to as acyl isethionates or acyloxyethanesulfonates.

Like the taurides, isethionates are a class of particularly mild anionic surfactants which, unlike ordinary soaps, retain their washing-active properties even in hard water.
Isethionates are obtained on an industrial scale reacting mixtures of carboxylic acids with salts of isethionic acid under acidic catalysis e. g. with methanesulfonic acid.

The mixtures of carboxylic acids are obtained from the hydrolysis of animal fats (tallow) or vegetable oils, preferably coconut oil, but also palm oil, soybean oil or castor oil.
Isethionates are solids which are often mixed with fatty acids (up to 30% by weight) to lower their freezing point.

Despite Isethionate's low water solubility (100ppm at 25 °C), the lower-priced sodium cocoylisethionate has found more widespread use than its well water-soluble ammonium salt (> 25 wt.% at 25 °C).
To solubilize the sparsely soluble isethionates and taurides, the formation of mixtures with amphoteric surfactants (such as cocamidopropyl betaine) are proposed.

From such mixtures, Isethionate is possible to prepare liquid, clear and transparent aqueous concentrates which are liquid at room temperature.
Isethionates are characterized by excellent skin compatibility, excellent foaming (even in hard water), good cleansing properties and a pleasant skin feel.
Isethionates are non-toxic and readily biodegradable.

However, in contrast to the taurides, they are not long-term stable outside a pH range of 5 to 8.
Isethionate is the alkanesulfonate that is the anion formed from isethionic acid by loss of a proton from the sulfo group; major microspecies at pH 7.3.
Isethionate is a conjugate base of an isethionic acid.

USES and APPLICATIONS of ISETHIONATE:
Isethionates are used in solid soaps (so-called syndet bars) and in other personal care products such as lotions, washing and shower gels, shampoos, liquid soaps, shaving creams, and other cosmetic and dermatological preparations.
Despite Isethionate's low water solubility (100ppm at 25 °C), the lower-priced sodium cocoylisethionate has found more widespread use than its well water-soluble ammonium salt (> 25 wt.% at 25 °C).

To solubilize the sparsely soluble isethionates and taurides, the formation of mixtures with amphoteric surfactants (such as cocamidopropyl betaine) are proposed.
Isethionate is commonly used in the personal care and cosmetics industry as a mild surfactant and cleansing agent.

Isethionate is especially valued in shampoos, facial cleansers, and body washes because it cleans effectively without stripping the skin of its natural oils.

One of the main applications of Isethionate is in sulfate-free formulations, where it serves as a gentler alternative to harsher surfactants.
Isethionate offers significant benefits for sensitive skin, as it has low irritation potential and is well tolerated by most skin types.
Isethionate helps create a rich and creamy lather, which improves the sensory experience of cleansing products.

-Personal Care & Cosmetics use of Isethionate:
Isethionate is used as a mild anionic surfactant in shampoos, body washes, syndet (synthetic detergent) bars, facial cleansers, and baby care products due to its gentle cleansing and foaming properties.
Sodium isethionate helps create stable, creamy lather with reduced irritation compared with traditional sulfate surfactants.

-Chemical Intermediate & Industrial Use of Isethionate:
Isethionic acid is a building block for other anionic surfactants, such as sodium lauroyl isethionate and sodium cocoyl isethionate (used in gentle soaps).
Its sulfonic acidity also finds limited niche uses in organic synthesis and biochemical pathways.

BENEFIT of ISETHIONATE:
Another benefit of isethionate is its ability to work well in hard water, maintaining good performance without excessive residue.
From a characteristics standpoint, Isethionate is known for its excellent dermatological compatibility.
Isethionate is chemically stable over a wide pH range, which makes it suitable for many different formulations.
Isethionate is water-soluble and easy to incorporate into both solid and liquid products.
Overall, isethionate is preferred in modern formulations that aim for mildness, effectiveness, and consumer comfort.

ISETHIONATES:
Proven Sulfate-free Surfactant Chemistry
Consumers expect cleansing products to provide rich foam with a pleasing after-feel.
The choice of surfactant in achieving this, especially in premium or specialist products, is key.

Comprehensive range of easy-to-use, mild surfactants and performance blends offers dense luxurious foams in:
*Shampoos
*Body and face washes
*Bath foams
*Shower gels
*Babycare

CLASSIFICATION & FUNCTIONALITY of ISETHIONATE:
Chemical Class: 
Anionic surfactant / sulfonate derivative.

Functional Class: 
Mild cleansing agent, surfactant, antistatic, skin‑conditioning ingredient (in personal care products).

Mechanism: 
Isethionic acid’s sulfonic acid group contributes to hydrophilicity; the sodium salt (sodium isethionate) balances charge and provides surface‑active properties.

CHEMICAL CHARACTERISTICS & BENEFITS of ISETHIONATE:
Mild Cleansing: 
Isethionate retains cleansing ability even in moderately hard water unlike simple soaps.

Skin Compatibility: 
Favored for sensitive skin products due to lower irritation potential.

Foam Quality: 
Isethionate produces stable, creamy foam used in syndet bars and shampoos.

Biodegradability: 
Generally considered more biodegradable and environmentally favorable than traditional sulfate surfactants.

ISETHIONIC ACID:
Isethionic Acid is a colorless, syrupy, strongly acidic liquid that can form detergents with oleic acid.
Isethionic acid (2-Hydroxyethanesulfonic acid) is an organosulfur compound.
Isethionic acid is widely distributed in animal species and in a few red algal species.

Isethionic acid is an alkanesulfonic acid in which the sulfo group is directly linked to a 2-hydroxyethyl group.
Isethionic Acid has a role as a human metabolite.
Isethionic Acid is a conjugate acid of an isethionate.

Isethionic acid is a metabolite found in or produced by Escherichia coli (strain K12, MG1655).
Isethionic Acid has been reported in Tichocarpus crinitus, Trypanosoma brucei, and Gayliella flaccida with data available.
Isethionic acid is an organosulfur compound containing an alkylsulfonic acid located beta to a hydroxy group.

Its discovery is generally attributed to Heinrich Gustav Magnus, who prepared Isethionic Acid by the action of solid sulfur trioxide on ethanol in 1833.
Isethionic Acid is a white water-soluble solid used in the manufacture of certain surfactants and in the industrial production of taurine.
Isethionic Acid is most commonly available in the form of its sodium salt (sodium isethionate).

USES and APPLICATIONS of ISETHIONIC ACID:
Isethionic acid is also used as a counter ion in certain pharmaceutical formulations, including the antimicrobials hexamidine and pentamidine.
Isethionic acid can be used as an anionic detergent and has anti-settlement activity against Balanus amphitrite.
Isethionic acid is a calcium binder and anionic detergent that enhances mitochondrial calcium binding capacity by competitively binding to calcium binding sites on the outer mitochondrial membrane.

SYNTHESIS ISETHIONIC ACID:
The original synthesis of Isethionic Acid, involving the reaction of sulfur trioxide with ethanol, has largely been replaced by more advanced methods.
An alternative production method involves the hydrolysis of carbyl sulfate, which is derived from the sulfonation of ethylene.
However the most common route is the reaction of ethylene oxide with aqueous sodium bisulfite, which produces the sodium salt (sodium isethionate).

REACTIONS ISETHIONIC ACID:
Isethionic acid is used as a starting material in the industrial production of taurine.
Dehydration of isethionic acid gives vinylsulfonic acid.

DERIVATIVES ISETHIONIC ACID:
Fatty acid esters of isethionic acid (such as sodium lauroyl isethionate and sodium cocoyl isethionate) are used as biodegradable anionic surfactants.
These materials are much milder to skin that other sulfate based surfactants (i.e. sodium lauryl sulfate) making them popular for use in make-up, shampoos and detergent bars including those made by Dove.

SODIUM ISETHIONATE:
Sodium isethionate is a mild anionic surfactant widely used in personal care products due to its gentle cleansing properties.
Overall, sodium isethionate provides mild cleansing, skin-friendly lather, formulation stability, and environmentally favorable properties, making it a preferred surfactant in sensitive skin and baby care applications.

Sodium 2-hydroxyethyl sulfonate (also: sodium isethionate) is the sodium salt of 2-hydroxyethane sulfonic acid (isethionic acid).
Sodium isethionate is a mild, anionic surfactant widely used in personal care and cleansing formulations.

Also known as isethionic acid sodium salt or sodium 2-hydroxyethyl sulfonate, Sodium isethionate features excellent water solubility, high compatibility with other surfactants, and a gentle, skin-friendly profile.
Sodium isethionate is often used as a raw material in the production of mild surfactants such as Sodium Cocoyl Isethionate (SCI), which are popular in sulfate-free shampoos, facial cleansers, and body washes.

USES and APPLICATIONS of SODIUM ISETHIONATE:
Sodium isethionate is a common ingredient in syndet bars, facial cleansers, baby shampoos, and body washes, where it helps produce a stable, creamy lather without stripping natural skin oils.
Its low irritation potential makes Sodium isethionate suitable for sensitive skin and baby care products, and it is often used as a safer alternative to harsher sulfate surfactants like sodium lauryl sulfate.

In cosmetic formulations, sodium isethionate acts as a surfactant, foaming agent, and skin-conditioning agent.
Sodium isethionate can also be combined with other surfactants, including amphoteric or nonionic types, to improve foam quality, texture, and product stability.

Because Sodium isethionate is highly water-soluble, it dissolves easily and disperses evenly in formulations, contributing to smooth, homogeneous creams, washes, and bars.
Beyond cosmetics, isethionic acid derivatives serve as intermediates in the production of other mild surfactants, such as sodium lauroyl isethionate, which is widely used in gentle cleansing bars and shampoos.

Sodium isethionate is also valued for its biodegradability and environmentally friendly profile, compared with conventional surfactants, which makes it attractive in green formulations.
Sodium isethionate is used as a hydrophilic head group in washing-active surfactants, known as isethionates (acyloxyethanesulfonates) due to its strong polarity and resistance to multivalent ions.

The main use of Sodium isethionate is the production of the isethionate class of surfactants.
These are readily foaming and particularly mild, making them suitable for cleaning sensitive skin and are therefore mainly used in baby soaps and shampoos.

Because of its pronounced skin compatibility Sodium isethionate is added to soaps and liquid skin cleansers with up to 15 parts by weight.
The addition of Sodium isethionate to electroplating baths allows higher current densities and lower concentrations than the much more expensive methane sulphonic acid with improved appearance.

-Personal Care and Cleansing Products use of Sodium isethionate:
Sodium isethionate is a key ingredient in syndet (synthetic detergent) bars, facial cleansers, and shampoos.
Sodium isethionate provides mild yet effective cleansing and helps maintain skin moisture without irritation.
When reacted with fatty acids, Sodium isethionate forms Sodium Cocoyl Isethionate (SCI) — a gentle surfactant highly favored in sulfate-free formulations.

-Hair and Skin Care Formulations use of Sodium isethionate:
Thanks to its excellent skin compatibility and low irritation potential, Sodium isethionate is used in:
Moisturizing body washes
Baby shampoos and soaps
Conditioning shampoos and facial foams
Sodium isethionate leaves skin feeling soft and smooth after washing.

-Industrial and Synthetic Applications of Sodium isethionate:
Sodium isethionate can serve as a hydrophilic intermediate in the synthesis of other surfactants, detergents, and specialty chemicals.
Sodium isethionate helps improve the water solubility and mildness of the final formulations.

KEY CHARACTERISTICS of SODIUM ISETHIONATE:
high water solubility, mildness on skin, compatibility with other ingredients, ability to produce stable foams, and functioning as a gentle cleansing agent.
Sodium isethionate is stable under normal formulation conditions but should be stored in a dry, cool environment to prevent moisture absorption due to its slight hygroscopicity.

PHYSICAL and CHEMICAL PROPERTIES of ISETHIONATE:
Molecular Weight:125.13 g/mol
XLogP3-AA:-1.7
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:4
Rotatable Bond Count:1
Exact Mass:124.99085481 Da
Monoisotopic Mass:124.99085481 Da
Topological Polar Surface Area:85.8 Ų
Heavy Atom Count:7

Formal Charge:-1
Complexity:104
Isotope Atom Count:0
Defined Atom Stereocenter Count:0
Undefined Atom Stereocenter Count:0
Defined Bond Stereocenter Count:0
Undefined Bond Stereocenter Count:0
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes

A) Isethionic Acid
Name:Isethionic acid
Systematic / IUPAC:2‑Hydroxyethane‑1‑sulfonic acid
CAS Number:107‑36‑8
Molecular Formula:C₂H₆O₄S
Molar Mass:126.13 g/mol
PubChem CID:7866
Appearance & Physical State:White solid (often water‑soluble)

Solubility:Soluble in water
Density:1.63 g/cm³
pKa:1.39
Chemical formula:C2H6O4S
Molar mass:126.13 g/mol
Density:1.63 g/cm3
Acidity (pKa):1.39

B) Sodium Isethionate (Common Form Used in Products)
Name:Sodium isethionate
Systematic / IUPAC:Sodium;2‑hydroxyethanesulfonate
CAS Number:1562‑00‑1
EC / EINECS Number:216‑343‑6
Molecular Formula:C₂H₅NaO₄S
Molar Mass:148.11 g/mol
PubChem CID:517063
Appearance:White fine powder / crystalline solid
Melting Point:191–196 °C

Density:1.62–1.76 g/cm³ at 20 °C
Bulk Density:800 kg/m³
Solubility:Readily soluble in water (clear, colorless solution)
pH:7.0–11.0
Stability:Stable under normal conditions; 
hygroscopic; 
incompatible with strong oxidizing agents or strong acids
Physical Condition (20°C):Thick
Store Under Inert Gas:Store under inert gas

Condition to Avoid:Hygroscopic
Reaxys Registry Number:3633992
PubChem Substance ID:87570669
MDL Number:MFCD00007534
Purity (Ion exchange titration):min. 98.0%
Physical State (20°C):Solid
Storage Temperature:Room Temperature (Recommended in a cool and dark place, <15°C)
Melting Point (reference):194 °C
Molecular Formula / Molecular Weight:C2H5NaO4S = 148.11

FIRST AID MEASURES of ISETHIONATE:
-Description of first-aid measures
*General advice:
Show this material safety data sheet to the doctor in attendance.
*If inhaled:
After inhalation: 
Fresh air.
*In case of skin contact: 
Take off immediately all contaminated clothing. 
Rinse skin with
water/ shower.
*In case of eye contact:
After eye contact: 
Rinse out with plenty of water. 
Call in ophthalmologist. 
Remove contact lenses.
*If swallowed:
After swallowing: 
Immediately make victim drink water (two glasses at most). 
Consult a physician.
-Indication of any immediate medical attention and special treatment needed.
No data available

ACCIDENTAL RELEASE MEASURES of ISETHIONATE:
-Environmental precautions:
Do not let product enter drains.
-Methods and materials for containment and cleaning up:
Cover drains. 
Collect, bind, and pump off spills. 
Observe possible material restrictions. 
Take up dry. 
Dispose of properly. 
Clean up affected area.

FIRE FIGHTING MEASURES of ISETHIONATE:
-Extinguishing media:
*Suitable extinguishing media:
Carbon dioxide (CO2) 
Foam 
Dry powder
*Unsuitable extinguishing media:
For this substance/mixture no limitations of extinguishing agents are given.
-Further information:
Prevent fire extinguishing water from contaminating surface water or the ground water system.

EXPOSURE CONTROLS/PERSONAL PROTECTION of ISETHIONATE:
-Control parameters:
--Ingredients with workplace control parameters:
-Exposure controls:
--Personal protective equipment:
*Eye/face protection:
Use equipment for eye protection. 
Safety glasses
*Body Protection:
protective clothing
*Respiratory protection:
Recommended Filter type: Filter A 
-Control of environmental exposure:
Do not let product enter drains.

HANDLING and STORAGE of ISETHIONATE:
-Conditions for safe storage, including any incompatibilities:
*Storage conditions:
Tightly closed. 
Dry.

STABILITY and REACTIVITY of ISETHIONATE:
-Chemical stability:
The product is chemically stable under standard ambient conditions (room temperature).
-Possibility of hazardous reactions:
No data available