Theophylline Sodium Glycinate Oral Solution (Monograph under this new title—to become official June 1,2005) (Current monograph title is Theophylline Sodium Glycinate Elixir) »Theophylline Sodium Glycinate Oral Solution contains an amount of theophylline sodium glycinate equivalent to not less than 93.0percent and not more than 107.0percent of the labeled amount of anhydrous theophylline (C7H8N4O2). Packaging and storage— Preserve in tight containers. USP Reference standards á11ñ USP Theophylline RS. Labeling— Label Oral Solution to state both the content of theophylline sodium glycinate and the content of anhydrous theophylline. Identification— Mix a volume of Oral Solution,equivalent to about 500mg of theophylline,with 10mLof 6Nammonium hydroxide,and evaporate on a steam bath to a volume of about 20mL.Neutralize with 6Nacetic acid to litmus,and cool,with stirring,to about 15.Collect the precipitate on a filter,wash with cold water,and dry at 105for 4hours:the theophylline so obtained melts between 270and 274,the procedure for Class Ibeing used (see Melting Range or Temperature á741ñ),and meets the requirements for Identificationtest Bunder Theophylline Sodium Glycinate. pHá791ñ: between 8.3and 9.1. Alcohol content,Method IIá611ñ: between 17.0%and 23.0%of C2H5OH. Assay— Buffer solution,Mobile phase,Internal standard solution,Standard preparation,and Chromatographic system— Prepare as directed in the Assayunder Theophylline. Assay preparation— Transfer an accurately measured volume of Oral Solution,equivalent to about 220mg of theophylline sodium glycinate,to a 100-mLvolumetric flask,dilute with water to volume,and mix.Transfer 10.0mLof this solution to a 100-mLvolumetric flask,add 20.0mLof Internal standard solution,dilute with Mobile phaseto volume,and mix. Procedure— Proceed as directed for Procedurein the Assayunder Theophylline.Calculate the quantity,in mg,of anhydrous theophylline (C7H8N4O2)in each mLof the Oral Solution taken by the formula: (1000C/V)(RU/RS), in which Vis the volume,in mL,of Oral Solution taken,and the other terms are as defined therein. (Official June 1,2005) Auxiliary Information— Staff Liaison:Karen A Russo,Ph.D.,Scientist Expert Committee:(PA1)Pharmaceutical Analysis 1 USP28–NF23Page 1903 Pharmacopeial Forum:Volume No.28(2)Page 378 Phone Number:1-301-816-8379