Alprazolam
Click to View Image
C17H13ClN4 308.76

4H-[1,2,4]Triazolo[4,3-][1,4]benzodiazepine, 8-chloro-1-methyl-6-phenyl-.
8-Chloro-1-methyl-6-phenyl-4H-s-triazolo[4,3-][1,4]benzodiazepine [28981-97-7].
» Alprazolam contains not less than 98.0 percent and not more than 102.0 percent of C17H13ClN4.
Caution—Care should be taken to prevent inhaling particles of Alprazolam and exposing the skin to it.
Packaging and storage— Preserve in tight containers, and store at controlled room temperature.
Identification—
B: The retention time of the major peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.
Loss on drying 731 Dry it at 105 for 1 hour: it loses not more than 0.5% of its weight.
Residue on ignition 281: not more than 0.5%.
Related compounds—
Diluent, Buffer, Mobile phase, and Standard preparation— Prepare as directed in Assay.
System suitability solution— Dissolve suitable quantities of USP Alprazolam RS, USP Alprazolam Related Compound A RS, and USP 2-Amino-5-chlorobenzophenone RS in Diluent to obtain a final concentration of 20 µg per mL of each.
Standard solution— Quantitatively dilute a suitable volume of the Standard preparation with Diluent to obtain a final solution having a known concentration of 0.25 µg per mL of alprazolam. [note—When stored in closed containers, the Standard solution is stable for 48 hours at room temperature.]
Test solution— Use the Assay stock preparation.
Chromatographic system— Prepare as directed in Assay. Chromatograph separately the System suitability solution and the Standard solution, and record the peak responses as directed for Procedure: the resolution, R, between alprazolam related compound A and alprazolam is not less than 2.0; and the relative standard deviation for the alprazolam peak in the Standard solution is not more than 5.0%.
Procedure— Separately inject equal volumes (about 20 µL) of the Standard solution and the Test solution into the chromatograph, and record the chromatograms for up to a minimum of five times the retention time of alprazolam. Identify the peaks using the approximate relative retention times given in Table 1. Calculate the quantity, in percent of each of the related compounds and any of the unspecified impurities by the formula:
100(1/F)(CS / CT)(ri / rS)
in which, F is the relative response factor for each impurity (given in Table 1); CS and CT are the concentrations of alprazolam, in µg per mL, in the Standard solution and the Test solution, respectively; ri is the peak response for the related compound or unspecified impurity in the Test solution chromatogram; and rS is the peak response for alprazolam in the Standard solution chromatogram. The relative response factors and the limits of the related compounds are given in Table 1.
Table 1
Related Compound Relative Retention
Time (RRT)
Relative
Response Factor (F)
Limit
% (w/w)
Alprazolam related compound A 0.8 0.76 NMT 0.15
Alprazolam 1.0 1.0
2-Amino-5-chlorobenzophenone 4.0 1.0 NMT 0.15
Individual unspecified impurity 1.0 NMT 0.10
Total impurities NMT 1.0
Assay—
Diluent— Prepare a mixture of acetonitrile and water (1:1).
Buffer— Dissolve 1.36 g of monobasic potassium phosphate (KH2PO4) in 1 L of water, and mix.
Mobile phase— Prepare a mixture of filtered and degassed acetonitrile and Buffer (1:1).
Standard preparation— Dissolve an accurately weighed quantity of USP Alprazolam RS in Diluent to obtain a solution having a known concentration of 25 µg per mL of alprazolam. [note—When stored in closed containers, the Standard preparation is stable for 48 hours at room temperature.]
Assay stock preparation— Dissolve an accurately weighed quantity of Alprazolam in Diluent to obtain a solution having a known concentration of 250 µg per mL of alprazolam. Sonicate for about 1 minute. [note—When stored in closed containers, the Assay stock preparation is stable for 24 hours at room temperature.]
Assay preparation— Dilute a suitable volume of the Assay stock preparation with Diluent to obtain a solution having a known concentration of about 25 µg per mL of alprazolam [note—When stored in closed containers, the Assay preparation is stable for 48 hours at room temperature.]
Chromatographic system— The liquid chromatograph is equipped with a 231-nm detector and a 4.6-mm × 25-cm column that contains packing L1. The flow rate is about 1 mL per minute. The column temperature is maintained at 40. Chromatograph the Standard preparation, and record the peak responses as directed for Procedure: the tailing factor is not more than 2.0 for the alprazolam peak, and the relative standard deviation of the alprazolam peak is not more than 2.0%.
Procedure— Separately inject equal volumes (about 20 µL) of the Standard preparation and the Assay preparation into the chromatograph, and measure the responses for the alprazolam peak. Calculate the quantity, in percent of C17H13ClN4 in the portion of Alprazolam taken by the formula:
100(CS / CU)(rU / rS)
in which, CS and CU are the concentrations of alprazolam, in µg per mL, in the Standard preparation and the Assay preparation, respectively; and rU and rS are the peak responses obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Ravi Ravichandran, Ph.D.
Senior Scientist
1-301-816-8330
(MDPP05) Monograph Development-Psychiatrics and Psychoactives
Reference Standards Lili Wang, Technical Services Scientist
1-301-816-8129
RSTech@usp.org
USP32–NF27 Page 1454
Pharmacopeial Forum: Volume No. 33(5) Page 868
Chromatographic Column—
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.