Sodium Carboxymethylcellulose Viscosity

Sodium carboxymethylcellulose is Hsted in the 1990 United States Pharmacopeia under the categories of pharmaceutic aid (suspending agent, tablet binder, viscosity-increasing agent), and cathartic tablets. 

Many viscosity enhancers are also considered to be bioadhesive and putative bioadhesive polymer gels, including methylcellulose, sodium carboxymethylcellulose, chitosan, Carbopol 934P (one of the carbomers)... 

Viscosity various grades of carboxymethylcellulose sodium are commercially available that have differing aqueous viscosities see Table 111. Aqueous 1% w/v solutions with viscosities of 5-13 000 mPas (5-13 000 cP) may be obtained. An increase in concentration results in an increase in aqueous solution viscosity. Prolonged heating at high temperatures will depolymerize the gum and permanently decrease the viscosity. The viscosity of sodium carboxymethylcellulose solutions is fairly stable over a pH range of 4-10. The optimum pH range is neutral. See Section 11. 

Khan KA, Rhodes CT. Evaluation of different viscosity grades of sodium carboxymethylcellulose as tablet disintegrants. Pharm Acta Helv 1975 50 99-102. 

Bugaj J, Gorecki M. Kinetics of dynamic viscosity changes of aqueous sodium carboxymethylcellulose and sodium alginate solutions. Pharmazie 1995 50(11) 750—752. 

Other non-ionic cellulose ethers which have been stndied in the formulation of hydrophilic matrices include high viscosity grades of hydroxypropylcellulose (HPC) and hydroxyethylcellulose (HEC) [24]. The ionic cellulose ether, sodium carboxymethylcellulose (Na CMC), with low or medium viscosity grades has... 

Although untreated starches do not swell sufficiently, certain modified forms, such as sodium starch glycolate, do swell in cold water and are better as disintegrants. Various cellulose derivatives, including methylcellulose and carboxymethylcellulose, have been used in this role, but with limited success due to the marked increase in viscosity they produce around the dispersing tablet mass. 

Prepare 500 mL of a 2% solution of carboxymethylcellulose, sodium salt, in water in the manner described in the U.S. Pharmacopeia reference above. Since the solution preparation is time-consuming, your instructor may prepare it ahead of time. Using a rotational viscometer with an appropriate spindle and a constant temperature bath, measure the viscosity of this solution at various temperatures. Plot viscosity vs. temperature. 

MCC and carboxymethylcellulose sodium Avicel RC-581, RC-591, CL-611 FMC BioPolymer, Newark, Delaware, U.S.A. Viscosity regulator and modifier, thixotropic characteristics, heat and freeze-thaw stable, long shelf-life stability, lengthy hydration times eliminated, stable at pH range 4-11... 

Carboxymethylcellulose calcium is also used in other applications similarly to carboxymethylcellulose sodium for example, as a suspending or viscosity-increasing agent in oral and topical pharmaceutical formulations. Carboxymethyl-... 

Carboxymethylcellulose sodium is widely used in oral and topical pharmaceutical formulations, primarily for its viscosity-increasing properties. Viscous aqueous solutions are used to suspend powders intended for either topical application or oral and parenteral administration. Carboxymethylcellulose sodium may also be used as a tablet binder and disin-tegrant, and to stabilize emulsions. ... 

Carboxymethylcellulose sodium may be sterilized in the dry state by maintaining it at a temperature of 160°C for 1 hour. However, this process results in a significant decrease in viscosity and some deterioration in the properties of solutions prepared from the sterilized material. 

Grades are typically classified as being of low, medium, or high viscosity. The degree of substitution and the maximum viscosity of an aqueous solution of stated concentration should be indicated on any carboxymethylcellulose sodium labeling. 

Carboxymethylcellulose sodium is used in oral, topical, and some parenteral formulations. It is also widely used in cosmetics, toiletries, and food products, and is generally regarded as a nontoxic and nonirritant material. However, oral consumption of large amounts of carboxymethylcellulose sodium can have a laxative effect therapeutically, 4-1 Og in daily divided doses of the medium- and high-viscosity grades of carboxymethylcellulose sodium have been used as bulk laxatives. " ... 

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