INCI: Carbomer 

CAS No: 9007-20-9 / 9003-01-4

Synonyms: -Carbopol: Carbomer. Carbomer. Carboxypolymethylene. Carpolene. Carboxyvinyl polymer. Polyacrylic acid.

Function: Emulsion stabilizer / viscosity / gelling control.

Molecular formula: [-CH2-CH (COOH) -] n

Molecular Weight: It has been estimated at 104,400 for the Carbopol 940.

Description:

Carbopolols are synthetic polymers of acrylic acid, high molecular weight and anionic character, which give rise to dispersions in aqueous, hydroalcoholic and different organic solvents. There are different types of Carbopol, which are designated by a number, but the most commonly used in pharmacy are Carbopol 934 and Carbopol 940. Those who carry the letter P after the number means that they are of high purity, with a content Residual benzene, which makes them suitable for oral use (eg as a binder in tablets).

Properties and uses:

Carbopol is used as emulsifying, viscosifying, suspending and gelling agent in formulas such as solutions, suspensions, creams, gels, and ointments, which can be administered ophthalmic, rectal, and topical. As an emulsifier it is used in the production of O / W emulsions for topical use, when it is desired to reduce the fat content.

As gellant, the carbomers form transparent neutral gels (to form the gel it is necessary to neutralize the Carbopol with a base of the triethanolamine type or a solution of 10% sodium hydroxide). Transparency depends on the solvents and the active ingredients used. It is also used as a binder in the tablet formulation. In magistral formulation, the acrylic gels of

Carbopol are usually the first choice, since except for their incompatibilities are the best rheological characteristics have.

Carbopol gel is an extensible non-greasy base, which increases the absorption of the incorporated active ingredients. It can be incorporated into most emulsions, allowing the thickening of the aqueous phase (cremigels). The maximum viscosity is obtained at pH 6-11.

Carbopol gels support up to 30-40% of maximum alcohol in their formulations. It is a base used in antiseborreic, moisturizing, and revitalizing agents. It is a skin protector against fats and organic solvents. Y is a secondary emulsifier to increase the viscosity of suppressions and shampoos.

It is a thermostable gel, so it can be sterilized to the autoclave. One of the applications is the formulation of fluid gels for artificial tears, in the treatment of dry eye. Reactions of the carbomers with basic drugs such as ephedrine form derivatives which can be incorporated into gels, which is useful in the formulation of long-acting medicaments.

The so-called "ultrasonic conducting gel" or "contact gel for ultrasound" is an aqueous or hydroalcoholic gel of Carbopol 940 to which more or less alcohol is added as desired more or less refreshing. A dye may also be added. In addition, Carbopol is used in the cosmetic industry.

Dosage:

As the gelling agent: 0.5-2%
-As emulsifying agent: 0,1
-0.5% -As suspending agent: 0.1-1%
-As binder in tablets: 0.75 - 3%
-As controlled release agent: 5 - 30%
-In aqueous ointments or base gels 0.5 - 5%
-In artificial tears: 0.2
-0.3% Gel consistency can be increased by increasing the Carbopol ratio (up to 5%).

Incompatibilities: Cationic substances (eg neomycin sulfate, procaine hydrochloride, diphenhydramine hydrochloride, cationic polymers, etc.), electrolytes and metal ions (especially sodium, calcium, aluminum, zinc, magnesium, and iron), strong acids or bases PH less than 6 or greater than 9-11), phenol, resorcinol, and UV radiation.

Storage: In tightly closed containers. PROTECTING LIGHT AND MOISTURE