Amphetamine Sulfate Tablets
»Amphetamine Sulfate Tablets contain not less than 93.0percent and not more than 107.0percent of the labeled amount of (C9H13N)2·H2SO4.
Packaging and storage—
Preserve in well-closed containers.
Identification—
Macerate a quantity of powdered Tablets,equivalent to about 50mg of amphetamine sulfate,with 10mLof water for 30minutes,and filter into a small flask.To the filtrate add 3mLof 1Nsodium hydroxide.Cool to about 10
to 15,add 1mLof a mixture of 1volume of benzoyl chloride and 2volumes of absolute ether,insert the stopper,and shake well for 3minutes.Filter the precipitate,wash with about 15mLof cold water,and recrystallize twice from diluted alcohol:the crystals of the benzoyl derivative of amphetamine so obtained,after drying at 80for 2hours,melt between 131and 135,the procedure for Class Ibeing used (see Melting Range or Temperature á741ñ).
to 15,add 1mLof a mixture of 1volume of benzoyl chloride and 2volumes of absolute ether,insert the stopper,and shake well for 3minutes.Filter the precipitate,wash with about 15mLof cold water,and recrystallize twice from diluted alcohol:the crystals of the benzoyl derivative of amphetamine so obtained,after drying at 80for 2hours,melt between 131and 135,the procedure for Class Ibeing used (see Melting Range or Temperature á741ñ).
Dissolution,Procedure for a Pooled Sample á711ñ—
Medium:
water;500mL.
Apparatus 1:
100rpm.
Time:
45minutes.
Mobile phase—
Dissolve 1.1g of sodium 1-heptanesulfonate in 575mLof water.Add 25mLof dilute glacial acetic acid (14in 100)and 400mLof methanol.Adjust by the dropwise addition of glacial acetic acid to a pHof 3.3±0.1,if necessary,filter,and degas the solution.Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).
Chromatographic system
(see Chromatography á621ñ)—The liquid chromatograph is equipped with a 254-nm detector and a 3.9-mm ×30-cm column that contains packing L1.The flow rate is about 1mLper minute.Chromatograph replicate injections of the Standard solution,and record the peak responses as directed for Procedure:the relative standard deviation is not more than 2.0%.
Procedure—
Inject a volume (about 500µL)of a filtered portion of the solution under test into the chromatograph,record the chromatogram,and measure the response for the major peak.Calculate the quantity of (C9H13N)2·H2SO4dissolved in comparison with a Standard solution having a known concentration of USP Dextroamphetamine Sulfate RSin the same medium and similarly chromatographed.
Tolerances—
Not less than 75%(Q)of the labeled amount of (C9H13N)2·H2SO4is dissolved in 45minutes.
Uniformity of dosage units á905ñ:
meet the requirements.
Assay—
Standard preparation—
Prepare as directed under Amphetamine Assay á331ñ.
Assay preparation—
Weigh and finely powder not fewer than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 5mg of amphetamine sulfate,to a 100-mLbeaker,add 2mLof hydrochloric acid solution (1in 100),swirl gently to wet the powder thoroughly,warm on a steam bath for about 1minute,with occasional gentle swirling,and cool.Add 3g of purified siliceous earth,and mix until a fluffy mixture is obtained.
Procedure—
Proceed as directed under Amphetamine Assay á331ñ.Calculate the quantity,in mg,of (C9H13N)2·H2SO4in the portion of Tablets taken by the formula:
0.01C[(AU257-AU280)/(AS257-AS280)],
in which Cis the concentration,in µg per mL,of USP Dextroamphetamine Sulfate RSin the Standard preparation.
Auxiliary Information—
Staff Liaison:Salvador C.Salado,M.S.,Scientist and Latin American Liaison
Expert Committee:(PA3)Pharmaceutical Analysis 3
USP28–NF23Page 149
Pharmacopeial Forum:Volume No.30(1)Page 54
Phone Number:1-301-816-8165