Tetracaine Hydrochloride for Injection »Tetracaine Hydrochloride for Injection contains not less than 90.0percent and not more than 110.0percent of the labeled amount of tetracaine hydrochloride (C15H24N2O2·HCl). Packaging and storage— Preserve in Containers for Sterile Solidsas described under Injections á1ñ,preferably of Type Iglass. USP Reference standards á11ñ USP Endotoxin RS.USP Tetracaine Hydrochloride RS. Completeness of solution á641ñ A10-mg portion dissolves in 1mLof water in not more than 2seconds to yield a colorless solution free from undissolved solid. Constituted solution— At the time of use,it meets the requirements for Constituted Solutionsunder Injections á1ñ. Identification— A: Ultraviolet Absorption á197UñSolution: the solution employed for measurement of absorbance in the Assay. B: It responds to Identificationtest Bunder Tetracaine Hydrochloride. Bacterial endotoxins á85ñ It contains not more than 0.7USP Endotoxin Unit per mg of tetracaine hydrochloride. Uniformity of dosage units á905ñ: it meets the requirements employing the following method. Standard preparation— Prepare as directed in the Assayunder Tetracaine Hydrochloride in Dextrose Injection. Test preparation— Transfer the contents of one container,with the aid of water,to a 200-mLvolumetric flask,add water to volume,and mix.Pipet a portion of this solution,equivalent to about 1mg of tetracaine hydrochloride,to a 100-mLvolumetric flask,add 5mLof dilute hydrochloric acid (1in 200)and 10mLof Buffer No.6,10percent,pH6.0(see Phosphate Buffers and Other Solutionsunder Antibiotics—Microbial Assays á81ñ),add water to volume,and mix. Procedure— Proceed as directed for Procedurein the Assay,except to use the Test preparationinstead of the Assay preparation. Calculate the quantity,in mg,of C15H24N2O2·HCl in each container taken by the formula: 20(C/V)(AU/AS), in which Vis the volume,in mL,of the portion used in the Test preparation,AUis the absorbance of the Test preparation,and Cand ASare as defined in the Assay. pHá791ñ: between 5.0and 6.0,in a solution (1in 100). Water,Method Iá921ñ: not more than 2.0%. Residue on ignition— Weigh accurately about 500mg,transfer to a beaker,and dissolve in 10mLof methanol.Filter through paper previously washed with methanol,collecting the filtrate in an ignited and tared crucible and washing the beaker and the filter paper with 25mLto 30mLof methanol.Evaporate with the aid of heat and a current of air to dryness,and proceed as directed under Residue on Ignition á281ñ,beginning with “Heat,gently at first.”Not more than 0.1%of residue is found. Chromatographic purity— Dissolve an accurately weighed quantity of Tetracaine Hydrochloride for Injection in water to obtain a test solution containing 50mg per mL,and proceed as directed in the test for Chromatographic purityunder Tetracaine,beginning with “Prepare a Standard solution.” Other requirements— It meets the requirements for Sterility Tests á71ñand Labelingunder Injections á1ñ. Assay— Standard preparation— Prepare as directed in the Assayunder Tetracaine Hydrochloride in Dextrose Injection. Assay preparation— Transfer to a tared 20-mLbeaker the contents of a sufficient number of containers of Tetracaine Hydrochloride for Injection to yield about 100mg of tetracaine hydrochloride.Weigh immediately,and transfer with the aid of water to a 500-mLvolumetric flask.Add water to volume,and mix.Transfer 5.0mLto a 100-mLvolumetric flask,add 5mLof dilute hydrochloric acid (1in 200)and 10mLof Buffer No.6,10percent,pH6.0(see Phosphate Buffers á81ñ),then add water to volume,and mix. Procedure— Concomitantly determine the absorbances of the Assay preparationand the Standard preparationat the wavelength of maximum absorbance at about 310nm,with a suitable spectrophotometer,using water as the blank.Calculate the quantity,in mg,of C15H24N2O2·HCl in the portion of Tetracaine Hydrochloride for Injection taken by the formula: 10C(AU/AS), in which Cis the concentration,in µg per mL,of USP Tetracaine Hydrochloride RSin the Standard preparation,and AUand ASare the absorbances of the Assay preparationand the Standard preparation,respectively. Auxiliary Information— Staff Liaison:Karen A Russo,Ph.D.,Scientist Expert Committee:(PA1)Pharmaceutical Analysis 1 USP28–NF23Page 1882 Phone Number:1-301-816-8379