Methylcellulose surfactancy

Benzalkonium chloride IM, inhalation, nasal, ophthalmic, otic, topical Citrate, methylcellulose, surfactants, some plastics, some rubbers... 

Among the polymers used in lens comfort solutions are polyvinyl alcohol, polyvinylpyrrolidone, dextran, and various cellulose derivatives such as hydroxyethyl cellulose, hydroxypropyl cellulose, and hydroxypropyl methylcellulose. Surfactants include certain poloxamer and poloxamine compounds. Other normal components comprise appropriate preservative(s) as well as buffering and tonicity-adjusting agents. 

Preservatives such as sodium benzoate, sorbic acid, and methyl and propyl parabens have been used in liquid and semisolid dosage forms. There have been reports that the parabens have been inactivated when used in the presence of various surfactants. This loss of activity was thought to be due to the formation of complexes between the preservative and the surfactant. The interaction between polysorbate (Tween) 80 and the parabens has been demonstrated by a dialysis technique (Ravin and Radebaugh, 1990). It has also been shown that molecular complexes form when the parabens are mixed with polyethylene glycol (PEG) and methylcellulose. The degree of binding was less than that observed with Tween 80. Sorbic acid also interacts with Tweens but does not interact with PEGs. The quaternary ammonium compounds are also bound by Tween 80, which reduces their preservative activity. 

Polysaccharides possess surfactancy to varying degrees. Methylcellulose is a very efficient protective colloid at 0.01% (Dow Chemical Co., 1990). Random coils (of xanthan) are more surface active than helices (Young and Torres, 1989). 

Benzyl alcohol Injections, oral, topical, vaginal Oxidizing agents, strong acids, nonionic surfactants, methylcellulose, some plastics... 

Chlorocresol Topical Some plastics, rubber, nonionic surfactants, methylcellulose... 

At a concentration of 0.1 %, chlorocresol may be completely inactivated in the presence of nonionic surfactants, such as polysorbate 80. However, other studies have suggested an enhancement of antimicrobial properties in the presence of surfactants. Bactericidal activity is also reduced, due to binding, by cetomacrogol, methylcellulose, pectin, or cellulose derivatives. In emulsified or solubilized systems, chlorocresol readily partitions into the oil phase, particularly into vegetable oils and higher concentrations will be required for efficient preservation. ... 

Chloroxylenol has been reported to be incompatible with nonionic surfactants and methylcellulose. 

Polymeric gums are also important compounds for building viscosity in shampoos and conditioners. They are easily dispersed in water at common use levels of 0.5 to 1.5%. The most commonly used cellulose polymer is hydroxyethycellu-lose, which is compatible with anionic and cationic surfactants and stable over a wide pH range [24], Other cellulose polymers in use include methylcellulose and hydroxypropylmethylcellulose. 

Hardening of cement mortars modified with water-soluble polymers comprises both cement hardening by hydration as well as polymer solidification by coagulation and film formation. Whereas the effect of polymer dispersions on the microstructure formation is frequently studied [1], only little information is available about the effect of polymer solutions. In contrast to polymer dispersions, water-soluble polymers are dissolved in the mixing water on a molecular scale and no surfactants are needed. However, the addition of small amounts of water-soluble polymers (usually below 4%) also influences the properties of the hardened material [2], This paper deals with the effect of the presence of water-soluble polymers on the microstructure. The study is made by means of SEM investigation. Polyvinyl alcohol-acetate (PVAA), Methylcellulose (MC) and Hydroxyethylcellulose (HEC) are applied in a 1 % polymer-cement ratio. This study was part of the doctoral research of E. Knapen [3],... 

Ophthalmic delivery For administration of water-insoluble drugs into the eye, colloidal systems are used. Surface active polymers, such as polyvinyl alcohol, poloxamer, and methylcellulose are often added as particle stabilizers and viscosity enhancers. Particle size in such colloidal systems should not exceed 5-10 pm in diameter. Emulsions, liposomes, and micro- and nanoparticles, all stabilized by surfactants, are used in topical ophthalmic drug delivery [56]. For instance, an ophthalmic preparation of cyclosporin A, Restasis , is an emulsion stabilized by polysorbate 80 and polymer carbomer 1342. 

To improve wetting, surfactants with an HLB larger than 15 are used, such as sodium dioctyl sulfosuccinate (Aerosol OT ), ethoxylated castor oil, poloxamer, sodium salts of higher alcohol sulfates (sodium lauryl sulfate) and polysorbates, but also polymers with interfacial activity as, for example hydrogel formers as methylcellulose, hypromellose, etcetera. A further discussion of these substances can be found in Sects. 23.6 and 23.7. In practice, propylene glycol or a thickening agent will lower the interfacial tension to a sufficient extent. 

Cellulose derivatives, especially methylcellulose and hypromellose, usually cause a strong foam at preparation because they also possess surfactant activity. For the formulation of settling suspensions they are often unsuitable as they create a sediment that is difficult to disperse. They are used in suspensions and emulsions for oral use (see Sects. 5.4.6 and 5.4.7) at concentrations of 0.25-2.5 %. In... 

Methylcellulose hydroxypropylcellulose Salts flaking hydroxybenzoates strongly oxidising substances In cold water methylcellulose swells and disperse slowly to form a viscous dispersion hydroxypropylcellulose forms a clear liquid in cold water [5] Well Strong surfactant (foam forming)... 

It is also possible to carry out the polymerization at 0 °C under the vapor pressure of the monomer in water with methylcellulose as surfactant [533]. High monomer conversion of 95 to 98% was observed. The intrinsic viscosity of 2.26 dL/g (in DMF) corresponds to a molar mass of about 10 g/mol. By modifying the reaction conditions (temperature and pressure) the molar mass could be controlled and p varied between 0.5 and 5 dL/g. Bis(t-butyl) hyponitrite and bis(a,a-dimethylbenzyl) hyponitrite can also act as initiators however, the conversion to polymer is low [538]. Often higher melting point, and higher crystallinity was observed than for suspension-polymerized PVF2 [544]. 

Breuer and Robb (1972) studied the effect of polymer hydrophobicity on the interaction of polymer with surfactant. SDS was used as the anionic surfactant along with several different polymers polyvinyl acetate (PVAc), polyvinyl alcohol (PVA), polypropylene oxide (PPO), PEO, and methylcellulose (MeC). 

These are mainly in the preservation of foods, pharmaceuticals and cosmetics, although there is a certain sensitization potential. PHBA alkyl esters are also used for the in-can protection of technical functional fluids, when one looks for particular odourless and colourless preservatives. Using PHBA alkyl esters for the protection of non-ionic surfactant solutions one has to bear in mind that binding effects may occur which reduce the antimicrobial efficacy. This is valid for anionic alkaline detergent solutions, too. Macromolecules, e.g. saccharosee-sters, polyoxy-40-stearate, polyvinyl-pyrrolidone, methylcellulose and carboxymethylcellulose, are also able to... 

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