Benzocaine, Butamben, and Tetracaine Hydrochloride Gel
» Benzocaine, Butamben, and Tetracaine Hydrochloride Gel is Benzocaine, Butamben, and Tetracaine Hydrochloride in a suitable gel base. It contains not less than 90.0 percent and not more than 110.0 percent of the labeled amounts of benzocaine (C9H11NO2), butamben (C11H15NO2), and tetracaine hydrochloride (C15H24N2O2·HCl).
Packaging and storage—
Preserve in tight containers, and avoid freezing.
') + '&img=../../images/v35300/cas-94-09-7.gif',600,500);)
') + '&img=../../images/v35300/cas-94-25-7.gif',600,500);)
') + '&img=../../images/v35300/cas-136-47-0.gif',600,500);)
Identification—
The retention times of the major peaks in the chromatogram of the Assay preparation correspond to those in the chromatogram of the Standard preparation, as obtained in the Assay.
Minimum fill 
755
:
meets the requirements.
755:
meets the requirements.
Assay—
Diluent, Mobile phase, Standard preparation, and Chromatographic system—
Proceed as directed in the Assay under Benzocaine, Butamben, and Tetracaine Hydrochloride Topical Solution.
Assay preparation—
Transfer an accurately weighed portion of Gel, equivalent to about 1400 mg of benzocaine, to a 100-mL volumetric flask. Add about 75 mL of methanol, and mix. Sonicate for about 1 minute, dilute with methanol to volume, and mix. Transfer 10.0 mL of this solution to a second 100-mL volumetric flask, add about 75 mL of Diluent, shake, dilute with Diluent to volume, and mix.
Procedure—
Proceed as directed for Procedure in the Assay under Benzocaine, Butamben, and Tetracaine Hydrochloride Topical Solution. Calculate the individual quantities, in mg, of benzocaine (C9H11NO2), butamben (C11H15NO2), and tetracaine hydrochloride (C15H24N2O2·HCl) in the portion of Gel taken by the formula:
1000C(rU / rS)
in which C is the concentration, in mg per mL, of the appropriate Reference Standard in the Standard preparation, and rU and rS are the peak responses of the corresponding analyte 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 | Domenick Vicchio, Ph.D.
Senior Scientific Liaison 1-301-998-6828 |
(SM42010) Monographs - Small Molecules 4 |
| Reference Standards | RS Technical Services 1-301-816-8129 rstech@usp.org |
USP35–NF30 Page 2322