Carmustine for Injection
DEFINITION
Carmustine for Injection is a sterile lyophilized preparation of carmustine. It contains NLT 90.0% and NMT 110.0% of the labeled amount of carmustine (C5H9Cl2N3O2).
[Caution—Use appropriate surgical gloves, arm covers, and a dust mask. Perform all work under a fume hood approved for testing cytotoxic agents when possible. ]
IDENTIFICATION
•  A. Infrared Absorption 197F
Sample:  Melt a small portion of the sample in a suitable container in a controlled water bath or oven, and set the temperature between 33 and 40.
Standard:  A similar preparation of USP Carmustine RS
•  B. The retention time of the major peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.
ASSAY
Change to read:
•  Procedure
[Note—Prepare solutions in low-actinic glassware, and keep them refrigerated until use. ]
Mobile phase:  See the gradient table below.
Time
(min)
Water
(%)
Acetonitrile
(%)
0 90 10
2.5 90 10
7 40 60
8.5 90 10
10.5 90 10
Diluent:  Acetonitrile and water (1:3)
Standard stock solution:  2.0 mg/mL of USP Carmustine RS in acetonitrile
Standard solution:  0.2 mg/mL of USP Carmustine RS in Diluent, from Standard stock solution
Impurity standard stock solution:  0.1 mg/mL of USP Carmustine Related Compound A RS in acetonitrile
System suitability solution:  0.2 mg/mL of USP Carmustine RS and 0.002 mg/mL of USP Carmustine Related Compound A RS in Diluent, from the Standard stock solution and Impurity standard stock solution, respectively
Sample stock solution:  2.0 mg/mL of carmustine in acetonitrile, from Carmustine for Injection. [Note—Allow test vials to warm to room temperature in a desiccator for 1 h. ]
Sample solution:  0.2 mg/mL of carmustine in Diluent, from the Sample stock solution
Chromatographic system 
Mode:  LC
Detector:  UV 200 nm
Refrigerated autosampler temperature:  5
Column:  4.6-mm × 7.5-cm; 3-µm packing L1
Flow rate:  1.5 mL/min
Injection size:  20USP35 µL
System suitability 
Sample:  System suitability solution
[Note—The relative retention times for carmustine related compound A and carmustine are 0.5 and 1.0, respectively. ]
Suitability requirements 
Resolution:  NLT 2.0 between carmustine related compound A and carmustine
Tailing factor:  NMT 1.5 for the carmustine related compound A and carmustine peaks
Relative standard deviation:  NMT 2.0% for the carmustine related compound A and carmustine peaks
Analysis 
Samples:  Standard solution and Sample solution
Calculate the percentage of carmustine (C5H9Cl2N3O2) in the portion of Carmustine for Injection taken:
Result = (rU/rS) × (CS/CU) × 100
rU== peak area of the Sample solution
rS== peak area of the Standard solution
CS== concentration of carmustine in the Standard solution (mg/mL)
CU== nominal concentration of carmustine in the Sample solution (mg/mL)
Acceptance criteria:  90.0%–110.0%
PERFORMANCE TESTS
•  Uniformity of Dosage Units 905: Meets the requirements
IMPURITIES
Organic Impurities 
•  Procedure: Limit of Carmustine Related Compound A
Diluent, Impurity standard stock solution, System suitability solution, Sample solution, Chromatographic system, and System suitability:  Proceed as directed in the Assay.
Standard solution:  0.002 mg/mL of USP Carmustine Related Compound A RS in Diluent, from the Impurity standard stock solution
Analysis 
Samples:  Standard solution and Sample solution
Calculate the percentage of carmustine related compound A in the portion of Carmustine for Injection taken:
Result = (rU/rS) × [100 × CS/(CU × A)] × 100
rU== peak response of carmustine related compound A from the Sample solution
rS== peak response of carmustine related compound A from the Standard solution
CS== concentration of carmustine related compound A in the Standard solution (mg/mL)
CU== nominal concentration of carmustine in the Sample solution (mg/mL)
A== assay of Carmustine for Injection, as a percentage
Acceptance criteria 
Carmustine related compound A:  NMT 1.0%
SPECIFIC TESTS
•  Bacterial Endotoxins Test 85: NMT 0.95 USP Endotoxin Unit/mg of carmustine
•  Sterility Tests 71: Meets the requirements
•  pH 791: Between 4.0 and 6.8 in a constituted solution prepared as directed in the labeling
ADDITIONAL REQUIREMENTS
•  Packaging and Storage: Preserve as described in Injections 1, Containers for Sterile Solids at a temperature between 2 and 8.
•  Labeling: It meets the requirements in Injections 1, Labeling.
•  Constituted Solution: At time of use, it meets the requirements in Injections 1, Constituted Solutions.
•  USP Reference Standards 11
USP Carmustine RS Click to View Structure
Urea, N,N¢-bis(2-chloroethyl)-N-nitroso-;
1,3-Bis(2-chloroethyl)-1-nitrosourea.
    C5H9Cl2N3O2        214.05
USP Carmustine Related Compound A RS
1,3-Bis(2-chloroethyl) urea.
    C5H10Cl2N2O        185.05
USP Endotoxin RS
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Feiwen Mao, M.S.
Senior Scientific Liaison
1-301-816-8320
(SM32010) Monographs - Small Molecules 3
85 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
1-301-816-8339
(GCM2010) General Chapters - Microbiology
71 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
1-301-816-8339
(GCM2010) General Chapters - Microbiology
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USP35–NF30 Page 2506
Pharmacopeial Forum: Volume No. 36(6) Page 1508