CMC LG
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Carboxymethylcellulose sodium salt Product Number C 5678 Store at Room Temperature Replacement for Product Number 360384 Product Description CAS Number: 9004-32-4 Molecular weight: 90 kDa Degree of polymerization: 400 Degree of substitution: 0.65-0.90 (6.5-9.0 carboxymethyl groups per 10 anhydroglucose units). Sodium content: Approximately 8% by weight. Purity: 99.5% Synonym: CMC; Do not confuse this soluble carboxymethylcellulose with the insoluble cation exchange resins such as CM-Cellulose, Microgranular Form, Preswollen, Product No. C 4146. This product is a low viscosity carboxymethylcellulose (CMC); the viscosity of a 4% solution in water at 25 °C is 50-200 centipoise (cps). The viscosity is both concentration and temperature dependent. As the temperature increases, the viscosity decreases. As the concentratino increases, the viscosity increases. Low, medium and high viscosity carboxymethylcellulose (CMC) are all used as suspending agents. Low viscosity CMC is usually used in "thin" aqueous solutions. Medium viscosity CMC is used to make solutions that look like a syrup. High viscosity CMC is used to make a mixture, which resembles a cream or lotion. Precautions and Disclaimer For Laboratory Use Only. Not for drug, household or other uses. Preparation Instructions The product is soluble in water (40 mg/ml). The key to dissolving carboxymethylcellulose is to add the solid carefully to the water so that it is well dispersed (well-wetted). Adding the solid in portions may be necessary. Adding water to t he dry solid produces a "clump" of solid that is very difficult to dissolve; the solid must be added to the water. Stir gently or shake intermittently; do not stir constantly with a magnetic stirring bar. High heat is not needed and may actually slow down the solubilization process. A mixing device, such as an impeller-type agitator which produces a vortex, would allow the powder to be drawn into the liquid, but it may produce some shearing. Storage/Stability Under normal conditions, the effect of temperature on solutions of this product is reversible, so slight temperature variation has no permanent effect on viscosity. However, long periods of heating CMC solutions at high temperatures (autoclaving) will degrade the product and permanently reduce viscosity. CMC is therefore very difficult to sterilize. γ -Irradiation, like heating, will degrade CMC. High viscosity CMC is more adversely affected by autoclaving and irradiation than is low viscosity CMC. Filtering CMC solutions tends to leave a gel behind because the material is fibrous, so solutions cannot be sterile filtered.
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Transcript of CMC LG
8/6/2019 CMC LG
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Carboxymethylcellulose sodium salt
Product Number C 5678 Store at Room Temperature
Replacement for Product Number 360384
Product DescriptionCAS Number: 9004-32-4Molecular weight: 90 kDaDegree of polymerization: 400Degree of substitution: 0.65-0.90 (6.5-9.0carboxymethyl groups per 10 anhydroglucose units).Sodium content: Approximately 8% by weight.Purity: 99.5%Synonym: CMC; Do not confuse this solublecarboxymethylcellulose with the insoluble cationexchange resins such as CM-Cellulose, MicrogranularForm, Preswollen, Product No. C 4146.
This product is a low viscosity carboxymethylcellulose
(CMC); the viscosity of a 4% solution in water at 25 °Cis 50-200 centipoise (cps). The viscosity is bothconcentration and temperature dependent. As thetemperature increases, the viscosity decreases. As theconcentratino increases, the viscosity increases.
Low, medium and high viscositycarboxymethylcellulose (CMC) are all used assuspending agents. Low viscosity CMC is usually usedin "thin" aqueous solutions. Medium viscosity CMC isused to make solutions that look like a syrup. Highviscosity CMC is used to make a mixture, whichresembles a cream or lotion.
Precautions and DisclaimerFor Laboratory Use Only. Not for drug, household orother uses.
Preparation Instructions The product is soluble in water (40 mg/ml).The key to dissolving carboxymethylcellulose is to addthe solid carefully to the water so that it is welldispersed (well-wetted). Adding the solid in portionsmay be necessary. Adding water to the dry solidproduces a "clump" of solid that is very difficult todissolve; the solid must be added to the water. Stirgently or shake intermittently; do not stir constantlywith a magnetic stirring bar. High heat is not neededand may actually slow down the solubilization process.A mixing device, such as an impeller-type agitatorwhich produces a vortex, would allow the powder to bedrawn into the liquid, but it may produce someshearing.
Storage/StabilityUnder normal conditions, the effect of temperature onsolutions of this product is reversible, so slighttemperature variation has no permanent effect on
viscosity. However, long periods of heating CMCsolutions at high temperatures (autoclaving) willdegrade the product and permanently reduceviscosity. CMC is therefore very difficult to sterilize.
γ -Irradiation, like heating, will degrade CMC. Highviscosity CMC is more adversely affected byautoclaving and irradiation than is low viscosity CMC.Filtering CMC solutions tends to leave a gel behindbecause the material is fibrous, so solutions cannot besterile filtered.
8/6/2019 CMC LG
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ProcedureTo measure the viscosity of CMC solutions:Prepare a 2% (w/w) solution of CMC in water. Heat for
several hours at 37 C. Place in a shaker for one to twodays at 2-8 °C to completely dissolve the product.Bring the solution back to 25 C.Measure the viscosity with a Brookfield viscometerusing the following parameters:
Model: LVFSpindle: #3Speed: 60 rpm
Temperature: 25 °CContainer: 120 ml polybottleMultiplication factor: 20.
IRB / RXR 8/03
Sigma brand products are sold through Sigma-Aldrich, Inc.Sigma-Aldrich, Inc. warrants that its products conform to the information contained in this and other Sigma-Aldrich publications. Purchaser
must determine the suitability of the product(s) for their particular use. Additional terms and conditions may apply. Please see reverse side ofthe invoice or packing slip.
