Carbopol

Carbopol is widely used in cosmetic and pharmaceutical practice as a gel-former. Carbopol resins are hydrophilic polymers which swell in water solutions and transform into the gel form at neutralization. At the elaboration of special cosmetic preparations in which carbopol is used, the problem of raw materials compatibility appears. For example, some extracts of aromatic pectin containing materials destroy the gel structure of carbopol. High contents of bivalent metal ions, in particular calcium ions, destructively influence onto the gel-making ability of the system too. 

The aim of the investigation was to study the influence of calcium and sodium ions, pectin containing extracts of aromatic vegetative raw materials and mumio on the carbopol gelation to develop the procedure of calcium and sodium ions mass part determination in extracts of aromatic vegetative pectin containing raw materials to establish the macro- and microelement composition of mumio. 

Determination of Na " and Na" ions in raw cosmetic materials was conducted with the developed method of flame photometry. A necessity of development of method of samples preparation arose up in the work process, as this spicily-aromatic raw material contained pectin in amount 0.1-0.5% and that prevented preparation of samples by standard method of extracts dilution and required incineration of analyzed sample, time of analysis was increased in 60 times. It was established that CaCl, solution with the concentration 0,4 % caused destmctions of the carbopol gel. It was established that the addition of 0,1% CaCl, and 0,1% NaCl salts solutions into the system intensified the effect of negative action of these salts onto the gel stmcture and the gel destmcted completely. 

The determined macro- and microelement stmcture of mumio specifies onto the expediency of the application of this biologically active substance as a cosmetic raw material in the cosmetic compositions, which do not contain carbopol. The developed procedure for calcium and sodium ions determination in pectin-containing vegetative extracts is express and it is recommended for application at elaboration of cosmetic production compositions on the carbopol base. 

Uses, (see also under Perchlorate Propellants and Explosives). It is used in pyrotechnics to impart a bright red color to flames (Ref 3). A gel was made from 50g of Sr perchlorate, lOOg of me ale, and 4.6g of Carbopol 940 gelling agent. Five g of this gel burned for 10 mins with an intense red flame (Ref 11). A 66/34 mixt of Sr perchlorate/powd Al was tested as a photo-flash compn for both sea level and high altitude use (Ref 8). Another mixt of 50ml of me... 

The controlled flocculation method may be used in conjunction with the addition of a polymeric material to form a structured vehicle. After the formation of the floes, an aqueous solution of polymeric material, usually negatively charged, such as carboxy-methylcellulose or carbopol, is added. The concentration employed depends on the consistency desired for the suspension, which also relates to the size and density of the dispersed phase. Care must be taken to ensure the absence of any incompatibility between the flocculating agent and the polymer used for the formation of the structured vehicle. 

In an attempt to formulate an anhydrous, but water-soluble, semisolid base for potential ophthalmic use, five bases were studied [279]. The nonaqueous portion of the base was either glycerin or polyethylene glycols in high concentrations. The matrix used to form the phases included silica, Gantrez AN-139, and Carbopol 940. Eye irritation results were not reported, but the authors studied representative bases from that research report and found them to be quite irritating in rabbit eyes. The irritation is believed to be primarily due to the high concentration of the polyols used as vehicles. 

A device designed to determine the transport of an epidermal growth factor from a Pluronic gel, a Carbopol gel, and a vanishing cream base was shown capable of demonstrating formulation-dependent release kinetics [22], This device consists of a release cell which has a membrane to minimize release due to mechanical breakdown and is placed in a stirred and temperature-controlled receptor fluid. 

Batcheler, C.L. and C.N. Challies. 1988. Loss of compound 1080 (sodium monofluoroacetate) from carbopol gel smeared on foliage to poison deer. N.Z. Jour. Forest. Sci. 18 109-115. 

C. Tas, C. K. Ozkan, A. Savaser, Y. Ozkan, U. Tasdemir, and H. Altunav. Nasal absorption of metoclopramide from different Carbopol 981 based formulations In vitro, ex vivo and in vivo evaluation. Eur J Pharm Biopharm 64 246-254... 

In the 1980s, Machid and Nagai [41] evaluated spray dosage forms based on hydroxypropyl cellulose (HPC) for the delivery of beclomethasone to treat recurrent and multiple apthae. Previously a double-layered tablet of HPC and Carbopol 934P was introduced in the market for the treatment of apthous stomatitis [41]. 

Nair and Chien [44] compared patches and tablets of different polymers (sodium carboxymethylcellulose, carbopol, polyethylene oxide, polymethyl vinyl ether-maleic anhydride, tragacanth) regarding their release characteristics of four drugs (chlorheximide, clotrimazole, benzocaine, and hydrocortisone). They observed sus-... 

Another type of novel mueoadhesive formulations was suggested to be submieron emulsions (o/w), bearing droplets eoated with Carbopol 940. These formulations have been shown to generate a 12-fold enhaneement in rats in the oral bioavailability of the antidiuretie peptide drug desmopressin [91]. 

Yahagi, R., Machida, Y., and Onishi, H., Mucoadhesive suppositories of ramosetron hydrochloride utilizing Carbopol, Int. J. Pharm., 193 205-212 (2000). 

Semisolid Dosage Forms The nature of the base (vehicle) used for the fabrication of semisolid dosage forms affects their hydrolytic stability. Increased degradation of benzylpenicillin sodium in hydrogels of various natural and semisynthetic polymers has been reported [14]. Also at pH 6 in Carbopol hydrogels, the percentage of undecomposed pilocarpine at equilibrium is a function of the apparent viscosity of the medium [15]. 

Use water to granulate a blend of clarithromycin and Carbopol 974P. 

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