A: Infrared Absorption á197Kñ.

B: The retention time of the principal peak in the chromatogram of the Assay preparationcorresponds to that in the chromatogram of the Standard preparation,as obtained in the Assay.

C: The RFvalue of the principal spot in the chromatogram of the Test solutioncorresponds to that of Standard solution 1,as obtained in the test for Related compounds.

Test solution: 10mg per mL,in water.

Adsorbent: 0.25-mm layer of chromatographic silica gel.

Spray reagent— Dissolve about 1.23g of p-anisidine and 1.66g of phthalic acid in 100mLof methanol.Store the solution in the dark and refrigerate to prevent discoloration.Discard if the solution becomes discolored.[Caution—p-Anisidine is toxic if inhaled or if absorbed through the skin. ]

Standard solution 1— Transfer about 10.0g of mannitol to a 100-mLvolumetric flask,dissolve in and dilute with water to volume,and mix.

Standard solution 2— Transfer about 40.0mg of fructose and 10.0g of mannitol to a 100-mLvolumetric flask,dissolve in 25mLof water,dilute with water to volume,and mix.

Test solution— Transfer about 2.5g of Sucralose,accurately weighed,to a 10-mLvolumetric flask,dissolve in about 5mLof methanol,dilute with methanol to volume,and mix.

Application volume: 5-µLportions separately applied in 1-µLincrements,allowing the plate to dry between applications.

Procedure— Proceed as directed for Thin-Layer Chromatographyunder Chromatography á621ñ.Spray the plate with Spray reagent,and heat the plate at 100±2for 15minutes.If the spot from Standard solution 1has darkened,repeat the test,heating for a shorter period of time.Immediately after heating,view the plate against a dark background:the color of the spot obtained from the Test solutionis not more intense than that obtained from Standard solution 2(0.1%).

Internal standard solution— Mix a suitable quantity of n-propyl alcohol with pyridine,and dilute quantitatively with pyridine to obtain a solution containing about 0.1µLof n-propyl alcohol per mL.

Standard solution— Transfer 2.0mLof methanol to a 100-mLvolumetric flask,dilute with Internal standard solutionto volume,and mix.Transfer 1.0mLof this solution to a 100-mLvolumetric flask,dilute with Internal standard solutionto volume,and mix.

Test solution— Transfer about 2g of Sucralose,accurately weighed,to a 10-mLvolumetric flask,dilute with Internal standard solutionto volume,and mix.

Chromatographic system (see Chromatography á621ñ)—The gas chromatograph is equipped with a flame-ionization detector and a 4-mm ×2-m glass column packed with 80-to 100-mesh silanized support S6.The injection port is maintained at about 200,the detector is maintained at about 250,and the column is maintained at 150.Helium is used as the carrier gas,flowing at a rate of about 20mLper minute.Chromatograph the Standard solution,and record the peak responses as directed for Procedure:the relative standard deviation for replicate injections is not more than 2.0%.

Procedure— Separately inject equal volumes (about 1µL)of the Standard solutionand the Test solutioninto the chromatograph,record the chromatograms,and measure the areas for the major peaks.Calculate the percentage of methanol in the portion of Sucralose taken by the formula: in which 0.79is the specific gravity of methanol;Cis the concentration,in µLper mL,of methanol in the Standard solution;Wis the weight,in g,of Sucralose taken to prepare the Test solution;and RUand RSare the peak response ratios of the methanol peak relative to the n-propyl alcohol peak obtained from the Test solutionand the Standard solution,respectively:not more than 0.1%of methanol is found.

Adsorbent: 0.20-mm layer of octadecylsilanized chromatographic silica gel.The thin-layer chromatographic plate also has a preadsorbent zone.

Detection reagent— Prepare a solution of sulfuric acid in methanol (3in 20).

Standard solution 1— Quantitatively dissolve an accurately weighed quantity of USP Sucralose RSin methanol to obtain a solution having a known concentration of about 10.0mg per mL.

Standard solution 2— Transfer 0.5mLof Standard solution 1to a 10-mLvolumetric flask,and dilute with methanol to volume.

Test solution— Prepare a solution in methanol containing about 100.0mg of Sucralose per mL.

Developing solvent system: a mixture of sodium chloride solution (1in 20)and acetonitrile (7:3).

Application volume: 5µL.

Procedure— Proceed as directed for Thin-Layer Chromatographyunder Chromatography á621ñ.Spray the plate with Detection reagent.Heat the plate for 10minutes at 125:the RFvalue of the principal spot obtained from the Test solutioncorresponds to that obtained from Standard solution 1,and the color of any other single spot obtained from the Test solutionis not more intense than that of the principal spot obtained from the Standard solution 2(0.5%).

Mobile phase— Prepare a filtered and degassed mixture of water and acetonitrile (17:3).Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).

Standard preparation— Dissolve an accurately weighed quantity of USP Sucralose RSin Mobile phase,and dilute quantitatively,and stepwise if necessary,with Mobile phaseto obtain a solution having a known concentration of about 1mg per mL.

Assay preparation— Transfer about 25mg of Sucralose,accurately weighed,to a 25-mLvolumetric flask,dissolve in and dilute with Mobile phaseto volume,and mix.

Chromatographic system (see Chromatography á621ñ)—The liquid chromatograph is equipped with a refractive index detector and a 8-mm ×10-cm column that contains packing L1.Maintain the flow rate at about 1.5mLper minute,so that the retention time for the sucralose peak is about 9minutes.Chromatograph the Standard preparation,and record the peak responses as directed for Procedure:the relative standard deviation for replicate injections is not more than 2.0%.

Procedure— Separately inject equal volumes (about 20µL)of the Standard preparationand the Assay preparationinto the chromatograph,record the chromatograms,and measure the areas for the major peaks.Calculate the quantity,in mg,of C12H19Cl3O8in the portion of Sucralose taken by the formula: in which Cis the concentration,in mg per mL,of USP Sucralose RSin the Standard preparation;and rUand rSare the peak responses obtained from the Assay preparationand the Standard preparation,respectively.