Oxazepam Capsules
DEFINITION
Oxazepam Capsules contain NLT 90.0% and NMT 110.0% of the labeled amount of C15H11ClN2O2.
IDENTIFICATION
• The retention time of the major peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.
ASSAY
• Procedure
Diluent:
Methanol and water (9:1)
Buffer:
8.5 g/L of monobasic potassium phosphate in water. Adjust with 1 N sodium hydroxide to a pH of 6.5.
Mobile phase:
Methanol and Buffer (3:2)
Standard solution:
0.1 mg/mL of USP Oxazepam RS in Diluent
Sample solution:
0.1 mg/mL of oxazepam in Diluent, from the contents of NLT 20 Capsules. [Note—Sonicate for 15 min and shake for 15 min. Pass through a filter of 0.45-µm pore size. ]
Chromatographic system
Mode:
LC
Detector:
UV 232 nm
Column:
4.6-mm × 15-cm; 5-µm packing L1
Flow rate:
1 mL/min
Injection size:
20 µL
Run time:
At least 1.7 times the retention time of oxazepam
System suitability
Sample:
Standard solution
Suitability requirements
Tailing factor:
NMT 1.5
Relative standard deviation:
NMT 2.0%
Analysis
Samples:
Standard solution and Sample solution
Calculate the percentage of C15H11ClN2O2 in the portion of Capsules taken:
Result = (rU/rS) × (CS/CU) × 100
| rU | = | = peak response from the Sample solution |
| rS | = | = peak response from the Standard solution |
| CS | = | = concentration of USP Oxazepam RS in the Standard solution (mg/mL) |
| CU | = | = nominal concentration of oxazepam in the Sample solution (mg/mL) |
Acceptance criteria:
90.0%–110.0%
PERFORMANCE TESTS
• Dissolution 
711
711
Medium:
0.1 N hydrochloric acid; 1000 mL
Apparatus 2:
75 rpm
Time:
60 min
Standard stock solution:
0.1 mg/mL of USP Oxazepam RS in methanol
[Note—Prepare NMT 30 min before use. ]
Standard solution:
0.01 mg/mL of USP Oxazepam RS in Medium from the Standard stock solution. [Note—Keep it at about 6
for the Analysis. This solution is stable for 72 h if kept refrigerated. ]
for the Analysis. This solution is stable for 72 h if kept refrigerated. ]
Sample solution:
Pass a portion of the solution under test through a suitable filter of 0.45-µm pore size. Keep it at about 6 for the Analysis.
for the Analysis.
Mobile phase:
Methanol, water, and glacial acetic acid (60:40:1)
Chromatographic system
Mode:
LC
Detector:
UV 232 nm
Column:
4-mm × 15-cm; packing L7
Flow rate:
2 mL/min
Injection size:
20 µL
System suitability
Sample:
Standard solution
Suitability requirements
Tailing factor:
NMT 1.5 for the oxazepam peak
Relative standard deviation:
NMT 3.0%
Analysis
Samples:
Standard solution and Sample solution
Tolerances:
NLT 75% (Q) of the labeled amount of C15H11ClN2O2 is dissolved.
• Uniformity of Dosage Units 905:
Meet the requirements
905:
Meet the requirements
IMPURITIES
Organic Impurities
• Procedure
Diluent, Buffer, and Mobile phase:
Proceed as directed in the Assay.
Standard solution:
2 µg/mL of USP Oxazepam RS in Diluent
Sample solution:
0.2 mg/mL of oxazepam in Diluent, from the contents of NLT 20 Capsules. [Note—Sonicate for 15 min and shake for 15 min. Pass through a filter of 0.45-µm pore size. ]
Chromatographic system:
Proceed as directed in the Assay.
Run time:
3.5 times the retention time of oxazepam
System suitability
Sample:
Standard solution
Suitability requirements
Tailing factor:
NMT 1.5
Relative standard deviation:
NMT 2.0%
Analysis
Samples:
Standard solution and Sample solution
Calculate the percentage of each impurity in the portion of Capsules taken:
Result = (rU/rS) × (CS/CU) × 100
| rU | = | = peak response of each individual impurity from the Sample solution |
| rS | = | = peak response of oxazepam from the Standard solution |
| CS | = | = concentration of USP Oxazepam RS in the Standard solution (µg/mL) |
| CU | = | = nominal concentration of oxazepam in the Sample solution (µg/mL) |
Acceptance criteria
Individual impurities:
See Impurity Table 1. [Note—Disregard peaks less than 0.05%. ]
Total impurities:
NMT 0.5%, not including 2-amino 5-chlorobenzophenone
Impurity Table 1
| Name | Relative Retention Time |
Acceptance Criteria, NMT (%) |
|---|---|---|
| Oxazepam | 1.0 | — |
| 2-Amino 5-chlorobenzophenone | 2.7 | 0.5 |
| Any individual unspecified degradation product | — | 0.1 |
ADDITIONAL REQUIREMENTS
• Packaging and Storage:
Preserve in well-closed containers.
• USP Reference Standards 11
11
USP Oxazepam RS 
') + '&img=../../images/v35300/cas-604-75-1.gif',600,500);)
Auxiliary Information—
Please check for your question in the FAQs before contacting USP.
| Topic/Question | Contact | Expert Committee |
|---|---|---|
| Monograph | Hariram Ramanathan, M.S.
Associate Scientific Liaison 1-301-816-8313 |
(SM42010) Monographs - Small Molecules 4 |
| 711 |
Margareth R.C. Marques, Ph.D.
Senior Scientific Liaison 1-301-816-8106 |
(GCDF2010) General Chapters - Dosage Forms |
| Reference Standards | RS Technical Services 1-301-816-8129 rstech@usp.org |
USP35–NF30 Page 4156
Pharmacopeial Forum: Volume No. 35(5) Page 1170