Powdered Cellulose
»Powdered Cellulose is purified,mechanically disintegrated cellulose prepared by processing alpha cellulose obtained as a pulp from fibrous plant materials.
Packaging and storage— Preserve in tight containers.
Labeling— The labeling indicates the nominal degree of polymerization value.Degree of polymerization compliance is determined using Identificationtest C.
Identification—
A: Prepare iodinated zinc chloride solution by dissolving 20g of zinc chloride and 6.5g of potassium iodide in 10.5mLof water.Add 0.5g of iodine,and shake for 15minutes.Place about 10mg of Powdered Cellulose on watch glass,and disperse in 2mLof iodinated zinc chloride solution:the substance takes on a violet-blue color.
B: Mix 30g with 270mLof water in a single-speed,high-speed (equal to or greater than 18,000rpm)power blender that has a clover-shaped jar design for 5minutes.The jar and blades meet the following specifications:the jar has an inside diameter of 7.0cm at the bottom and 9.2cm at the top,and an overall height of 21.9cm;and the 4blades are arranged so that 2of the blades are pointed up and 2are pointed down.Transfer 100mLof the dispersion to a 100-mLgraduated cylinder,and allow to stand for 1hour:the Powdered Cellulose settles in the cylinder,and a supernatant appears above the layer of the cellulose.
C: Transfer 0.25g of Powdered Cellulose,accurately weighed to 0.1mg,to a 125-mLconical flask.Proceed as directed for Identification test Bunder Microcrystalline Cellulose,beginning with “Add 25.0mLof water.”The degree of polymerization is between 440and 2250and is within the labeled specification.
Microbial limits á61ñ— The total aerobic microbial count does not exceed 1000cfu per g,the total combined molds and yeasts count does not exceed 100cfu per g,and it meets the requirements of the tests for absence of Staphylococcus aureusand Pseudomonas aeruginosaand for absence of Escherichia coliand Salmonellaspecies.
pHá791ñ— Mix 10g with 90mLof water,and allow to stand with occasional stirring for 1hour:the pHof the supernatant is between 5.0and 7.5.
Loss on drying á731ñ— Dry it at 105for 2hours:it loses not more than 6.0%of its weight.
Residue on ignition á281ñ: not more than 0.3%,calculated on the dried basis,the addition of sulfuric acid being omitted from the procedure.
Water-soluble substances— Mix 6.0g with 90mLof recently boiled and cooled water,and allow to stand with occasional stirring for 10minutes.Filter,with the aid of vacuum,discard the first 10mLof the filtrate,and pass the filtrate through the same filter a second time,if necessary,to obtain a clear filtrate.Evaporate a 15.0-mLportion of the filtrate in a tared evaporating dish to dryness without charring,dry at 105for 1hour,cool in a desiccator,and weigh:the difference between the weight of the residue and the weight obtained from a blank determination does not exceed 15.0mg (1.5%).
Ether-soluble substances— Place 10.0g in a chromatography column having an internal diameter of about 20mm,and pass 50mLof peroxide-free ether through the column.Evaporate the eluate to dryness in a previously dried and tared evaporating dish with the aid of a current of air in a fume hood.After all the ether has evaporated,dry the residue at 105for 30minutes,cool in a desiccator,and weigh:the difference between the weight of the residue and the weight obtained from a blank determination does not exceed 15.0mg (0.15%).
Auxiliary Information— Staff Liaison:Justin Lane,B.S.,Scientific Associate
Expert Committee:(EMC)Excipients:Monograph Content
USP28–NF23Page 2984
Pharmacopeial Forum:Volume No.30(4)Page 1437
Phone Number:1-301-816-8323