Surfactants in toothpastes

Surfa.cta.nt, The primary purpose of a surfactant in toothpaste is to create a foam while the teeth are bmshed. This foam provides an enjoyable sensation. Secondarily, the surfactant helps remove material dislodged by the toothbmsh, and it may have minor effects on plaque accumulation (see Surfactants). 

Detergents (i.e., surfactants) in toothpaste formulations have three main functions ... 

Uses Surfactant in toothpaste and pharmaceuticai preps. detergent and foaming agent in toiietries foaming agent, emuisifier in mfig. of toiiet bars emuision poiy-merization... 

Uses Surfactant In toothpaste, pharmaceutical, toiletry preps. wetting agent for agric. wettable powds. 

Uses Surfactant in toothpaste, pharmaceutical, and toiletry preps. 

A fluorinated surfactant in toothpastes containing potassium fluoride enhances fluoroapatite formation and inhibits caries [204]. A fluorinated surfactant formulation (1% Lodyne S-110), which consists of an amphoteric fluoroalky-laminocarboxylic acid and a nonionic fluoroalkylamide synergist, in the toothpaste increases enamel-fluoride interactions. A fluorinated surfactant in pharmaceutical formulations and in toothpaste must be nontoxic for the intended purpose. 

Konig, H., W. Strobel, Surfactants in toothpastes by HPLC (in English), Fresenius Z. Anal. Chem., 1988,337,435-438. 

In an extension of this work, Konig reports the determination of surfactants in toothpaste by HPLC (37). Here, one takes advantage of the knowledge that usually only one of a limited number of surfactants is present. The toothpaste is dissolved directly in the HPLC mobile phase, filtering out the abrasive and other insoluble matter. The characteristic retention time and peak pattern under a few standard HPLC conditions allow both identification and quantification of the surfactant. 

Sodium lauryl sarcosinate is very similar to the lauryl sulfate class of detergents and surfactants. The sulfate group is replaced with the amino acid sarcosinic acid, and the ammonium group is replaced with a sodium atom. The result is a detergent that is milder on the skin and oral membranes, and can be used in toothpastes without causing irritation of the gums. 

An important application of some sodium alcohol sulfates, particularly those based on C12 and C12-CI4 and produced in powder and needle forms, is as the basic surfactant ingredient in toothpastes. Sodium and triethanolamine lauryl sulfates are also components of shaving creams. 

Contact of surfactants with the skin and mucus membranes occurs either accidentally or as a consequence of normal use. Examples of this normal and everyday use are cleaning formulations, shampoos, foam baths, and toothpastes. Again this contact is seldom made with individual surfactants, in this case alcohol sulfates and alcohol ether sulfates, but through formulated products. It is known that surfactants present significant interactions, so that mixed systems are generally less aggressive than their individual components. However, the effect of pure surfactants merits attention, particularly sodium dodecyl sulfate, which is commonly used as a reference for many studies because of its high purity and availability. 

Amnionic surfactants used in shampoos, cosmetics, toothpaste, and laundry products include linear alkylbenzenesulfonates (LAS), alcohol sulfates (AS), alcohol ethoxysulfates (AES), alcohol glycerol ether sulfonates, and alpha-olefin sulfates. Household end use of anionic surfactants in the United States was 7.3 X 105 metric tons in 1987 LAS, AS, and AES accounted for 98% of the total (I). 

The best-known sweetness inhibitor is sodium dodecyl sulfate (SDS), also known as sodium lauryl sulfate. This substance is a twelve carbon surfactant that is quite commonly used as a detergent in toothpaste. The observation is often made that after brushing one s teeth, the taste of orange juice is unusually bitter. This has been ascribed to the presence of SDS in the dentifrice (6 ). 

The more complex Lamepon and Igepon type of amides, including the sarcosine (iV-methj lycine) [107-97-1] and A/-methyl taurine (AJ-methylarmno-ethanesulfonate) types shown in Table 4, are used primarily as specialty surfactants in shampoo and toothpaste formulations. These rather complex stmctures have limited use in very specialized applications. 

Uses Germicide, fungicide detergents disinfectant deodorant laboratory reagent topical antiseptic antimicrobial, antistat, emulsifier, surfactant in cosmetics disinfectant for pharmaceuticals (germicidal cleansers, antiseptic shampoo and toothpaste, feminine hygiene prods.), veterinary and surgical instruments veterinary disinfectant for treatment of cuts, wounds, skin infections Manuf./Disthb. AMRESCO http //www.amresco-inc.com] Acros Org. http //www.acros.be]... 

Electrophoretic techniques, mainly capillary zone electrophoresis (CZE) and also capillary iso-tachophoresis (ITP) or micellar electrokinetic chromatography (MEKC) have been used in cosmetic analysis (e.g., determination of cationic surfactants in toiletries, parabens in different cosmetics, fluoride, and polyphosphates in toothpaste, hair dyes, or acid preservatives in cosmetic lotions). However, their use is less extensive than LC, probably because the... 

Two anionic surfactants are predominant in toothpaste formulations. These are SLS and sodium dodecylbenzene sulfonate (SDOBS) that exhibits excellent foaming properties. A good quality and quantity of foam may be obtained by mixing SLS and SDOBS. Sodium lauroyl sarcosinate (HjC (CH2)ioCON(CH3)CH2COONa) was used extensively in dentifrices, but was found to be a cause of oral mucosal irritation. Nowadays, its use is limited. Surfactants also play the role of inhibitor of enzymes responsible for tooth decay. 

Alkyl sulfates or primary alcohol sulfates (PAS), which were the first synthetic surfactants used in personal care in the United States, are mainly used in toothpaste formulations. As for the AES, the alkyl moiety is typically a mixture of Ci2-Cjg chains. According to the application, one can find sodium, ammonium, magnesium, or triethanolamine salts of fatty alcohol sulfuric acid. They are obtained by the sulfation of a fatty (natural or synthetic) primary alcohol with a mixture of air/SOj according to the following reaction ... 

This not only applies to shampoos but also to toothpaste, in which anionic surfactants can also be identified, depending on the product. The chromatogram shown in Fig. 9-130 clearly demonstrates that the method developed for the analysis of anionic surfactants in shampoos is also suited for the investigation... 

Solubilization of toxic substances may result in their enhanced absorption and, thus, the presence of surfactants in river and tap water could increase the absorption of the carcinogenic polycyclic compounds, which are generally insoluble in body fluids, as a result of their solubilization. The hazards of exposure to household surfactants, in washing-up liquids, in toothpaste and in water supplies should not be underestimated. In addition, the irritant effects of surfactants (cutaneous toxicity) present in many cosmetic products should be addressed, and this led to the introduction of surfactants that are milder to the skin. For more detail on surfactant toxicity, the reader should refer to the text by Attwood and Florence. 

SLS s foaming properties do have a use in dental care besides consumer satisfaction, although its performance does not rely upon it heavily. The foaming action allows the polishing agent in toothpaste to be suspended and the detergency properties to reach otherwise inaccessible areas and cavities in the mouth. SLS also shows antimicrobial effects on bacterial flora in the mouth and hence is the most commonly chosen surfactant for toothpastes. 

The viscosity of xanthan gum dispersions is not very sensitive to ionic strength and pH (pH 3-12). Xanthan gum is incompatible with cationic surfactants because it is an anionic polymer. It is used as a thickener in toothpastes [15], shampoos, liquid soaps, food applications, creams, and lotions. Examples of the use of xanthan gum as a thickener in dentifrice formulations are the patent applications WO 9725019 A1 [41] and JP 08295637 A2 [42]. Xanthan gum is available from suppliers such as Calgon, Rhone-Poulenc, and TIC Gum under the trade names Keltrol, Rhodicare, and Ticaxan, respectively. 

---