Lauryl硫酸钠和Laureth硫酸钠都是surfactants。They lower the表面张力of aqueous solutions, thereby, enhance the wetting of surfaces. Therefore, they are useful in cosmetic products such as soap, shampoo, shaving cream, mascara, moisturizer lotions, and sun cream. Also, they are in detergents, toothpaste, carpet cleaner, fabric glue, etc. In brief, they are important in these products because of their ability to remove oil and grease, for being good foaming agents, and are very cheap. However, the key difference between sodium lauryl sulfate and sodium laureth sulfate arises because sodium laureth sulfate doesn’t dissolve proteins in the tissues like Sodium lauryl sulfate.
What is Sodium Lauryl Sulfate?
Sodium lauryl sulfate or SLS has many synonyms, such as十二烷基硫酸钠（SDS），Lauryl硫酸钠，Lauryl硫酸钠钠盐，N-硫酸钠硫酸钠, etc. The structural formula of this compound is CH3-(CH2)11-o-so3-na+。It is popular as a good cleaning agent, thus, included in various cleaning products and toiletries that we use. However, the laboratory experiments have proven that SLS is a skin irritant. It causes severe damage to the normal skin by disturbing its natural balance. Therefore, skin becomes permeable to other chemical substances. Sensitive skins are most easily damaged by SLS, and longer term usage can cause itchy, cracked dry skins. Further, it becomes toxic if enters in oral route.
Also, sodium lauryl sulfate causes eye irritations too. Because of the skin irritations, people avoid using products with sodium lauryl sulfate. Hence, sodium laureth sulfate has replaced this compound. Shampoos with SLS may increase hair falling, and it makes hair thin. Using toothpaste with SLS cause mouth ulcers. However, SLS is not致癌。But, it can react with other chemicals in cosmetic products to produce nitrosamines which are carcinogenic.
Sodium lauryl sulfate is also an emulsifying and dispersing agent. Because of its emulsifying and thickening ability, we can use it as a food additive. Also, it is useful in the laboratories for nanoparticle preparation and for protein separation by electrophoresis (SDS—PAGEtechnique).
The molecular formula of sodium laureth sulfate is CH3-(CH2)10-CH2- （OCH2CH2)n-o-so3NA+。它以短形式流行。此外，这也是一种表面活性剂，因此与硫酸钠相同的目的有用。然而，Laureth硫酸钠比SLS不太刺激。
Sodium lauryl sulfate is an organic compound having the chemical formula CH3-(CH2)11-o-so3-na+。Laureth硫酸钠也是一种有机化合物，但具有化学式CH3-(CH2)10-CH2- （OCH2CH2)n-o-so3NA+。Lauryl硫酸钠和Laureth硫酸钠之间的关键区别在于，硫酸钠硫酸钠与Laureth硫酸钠相比更刺激。Hence, to avoid any skin irritations, the sodium lauryl sulfate in skincare products has been replaced by sodium laureth sulfate. Furthermore, as another important difference between sodium lauryl sulfate and sodium laureth sulfate, we can say that sodium lauryl sulfate can dissolve proteins in the tissues whereas sodium laureth sulfate doesn’t. This is the reason for the key difference between sodium lauryl sulfate and sodium laureth sulfate.
However, there are many uses of sodium lauryl sulfate such as a good cleaning agent, an emulsifying and dispersing agent, for nano particle preparation and for protein separation by electrophoresis whereas we can use sodium laureth sulfate as a component in skin and hair products, as a surfactant, etc.
概括– Sodium Lauryl Sulfate vs Sodium Laureth Sulfate
1. “Sodium Laureth Sulfate.” American Chemical Society.Available here
2. “Sodium Lauryl Sulfate.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine.Available here