Glucosamine Sulfate Potassium Chloride

(C6H14NO5)2SO4·2KCl 605.52
Bis(d-glucose, 2-amino-2-deoxy-), sulfate potassium chloride complex;    
Bis(2-amino-2-deoxy--d-glucopyranose) sulfate potassium chloride complex (,)     [38899-05-7].
Glucosamine Sulfate Potassium Chloride contains NLT 98.0% and NMT 102.0% of glucosamine sulfate potassium chloride [(C6H14NO5)2SO4·2KCl], calculated on the dried basis.
•  A. Infrared Absorption 197K
Sample:  Transfer 50 mg of Glucosamine Sulfate Potassium Chloride to a centrifuge tube, and dissolve in 2 mL of water. Add 0.5 mL of barium chloride TS, and centrifuge. Collect the supernatant, and evaporate to dryness. Dry the residue at 105 for 2 h.
Acceptance criteria:  The IR spectrum of the Sample matches that of a similar preparation of USP Glucosamine Hydrochloride RS, except that the addition of barium chloride TS is omitted..
•  C. The retention time of the glucosamine peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.
•  D. Sulfate: In the test for Content of Sulfate, after the addition of barium chloride TS a white precipitate is formed.
•  Procedure
Buffer:  In a 1-L volumetric flask, dissolve 3.5 g of dibasic potassium phosphate in water, add 0.25 mL of ammonium hydroxide, dilute with water to volume, and mix. Adjust with phosphoric acid to a pH of 7.5.
Mobile phase:  Acetonitrile and Buffer (75:25)
Diluent:  Acetonitrile and water (50:50)
Standard solution:  3.8 mg/mL of USP Glucosamine Hydrochloride RS in Diluent. Shake for 5 min by mechanical means to completely dissolve.
Sample solution:  Transfer 263 mg of Glucosamine Sulfate Potassium Chloride to a 50-mL volumetric flask. Dissolve in 30 mL of Diluent, and shake by mechanical means. Dilute with Diluent to volume.
Chromatographic system 
Mode:  LC
Detector:  UV 195 nm
Column:  4.6-mm × 15-cm; 5-µm packing L8
Column temperature:  35
Flow rate:  1.5 mL/min
Injection size:  10 µL
System suitability 
Sample:  Standard solution
[Note—The peak for the glucosamine moiety elutes at about 10 min. The chromatogram shows additional peaks near the void volume, due to the counter ions. ]
Suitability requirements 
Tailing factor:  NMT 2.0 for the glucosamine peak
Efficiency:  NLT 1500 theoretical plates
Relative standard deviation:  NMT 2.0%.
Samples:  Standard solution and Sample solution
Calculate the percentage of glucosamine sulfate potassium chloride [(C6H14NO5)2SO4·2KCl] in the portion of Glucosamine Sulfate Potassium Chloride taken:
Result = (rU/rS) × (CS/CU) × (Mr1/Mr2) × 100
rU== peak response from the Sample solution
rS== peak response from the Standard solution
CS== concentration of USP Glucosamine Hydrochloride RS in the Standard solution (mg/mL)
CU== concentration of Glucosamine Sulfate Potassium Chloride in the Sample solution (mg/mL)
Mr1== molecular weight of glucosamine sulfate potassium chloride, 605.52
Mr2== twice the molecular weight of glucosamine hydrochloride, 431.26
Acceptance criteria:  98.0%–102.0% on the dried basis
•  Content of Sulfate
Sample:  1 g of Glucosamine Sulfate Potassium Chloride
Analysis:  Transfer the Sample to a 250-mL beaker, and dissolve in 100 mL of water. Add 4 mL of 6 N hydrochloric acid. Heat the solution to boiling, and add, with constant stirring, sufficient boiling barium chloride TS to completely precipitate the sulfate. Add an additional 2 mL of barium chloride TS, and digest on a steam bath for 1 h. Pass the mixture through ashless filter paper. Transfer the residue quantitatively to a new filter, and wash the residue with hot water until no precipitate is obtained when 1 mL of silver nitrate TS is added to 5 mL of washing. Transfer the paper containing the residue to a tared crucible. Char the paper, without burning, and ignite the crucible and its contents to constant weight. Calculate the content of sulfate by multiplying the weight obtained by 0.4116.
Acceptance criteria:  15.5%–16.5%
•  Residue on Ignition 281: 26.5%–31.0%
•  Sodium: A solution (1 in 10), tested on a platinum wire, does not impart a pronounced yellow color to a nonluminous flame.
•  Arsenic, Method II 211: NMT 3 µg/g
•  Heavy Metals, Method II 231: NMT 10 ppm
•  Optical Rotation, Specific Rotation 781S
Sample solution:  35 mg/mL. Measure the specific rotation 3 h after preparation.
Acceptance criteria:  +47.0 to +53.0
•  pH 791
Sample solution:  20 mg/mL
Acceptance criteria:  3.0–5.0
•  Loss on Drying 731: Dry a sample at 105 for 2 h: it loses NMT 1.0% of its weight.
•  Packaging and Storage: Preserve in tight, light-resistant containers.
•  USP Reference Standards 11
USP Glucosamine Hydrochloride RS Click to View Structure
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