Homosalate
If you find any inaccurate information, please let us know by providing your feedback here
Tóm tắt nội dung
This article is compiled based on the United States Pharmacopeia (USP) – 2025 Edition
Issued and maintained by the United States Pharmacopeial Convention (USP)
C16H22O3 262.34
Benzoic acid, 2-hydroxy, 3,3,5-trimethylcyclohexyl ester;
3,3,5-Trimethylcyclohexyl salicylate CAS RN®: 118-56-9; UNII: V06SV4M95S.
1 DEFINITION
Homosalate contains NLT 90.0% and NMT 110% of C16H22O3, calculated on the as-is basis.
2 IDENTIFICATION
Change to read:
A. Spectroscopic Identification Tests 〈197〉, Infrared Spectroscopy: 197F (CN 1-May-2020)
3 ASSAY
Procedure
Standard solution: 5.0 mg/mL of USP Homosalate RS in chloroform
Sample solution: 5.0 mg/mL of Homosalate in chloroform
3.1 Chromatographic system
(See Chromatography 〈621〉, System Suitability.)
Mode: GC
Detector: Flame ionization
Column: 0.53-mm × 30-m column coated with a 1-µm lm of G27
Temperature
Injector: 270°
Detector: 270°
Column: See Table 1.
Table 1
Initial Temperature (°) | Temperature Ramp (°/min) | Final Temperature (°) | Hold Time at Final Temperature (min) |
70 | 6 | 220 | 5 |
Carrier gas: Hydrogen
Flow rate: 6 mL/min
Injection size: 1 µL
Split ratio: 1:10
3.2 System suitability
[Note—The relative retention times for the cis-isomer and the trans-isomer are about 0.98 and 1.0, respectively.]
Suitability requirements
Resolution: NLT 1.0 between the cis-isomer and the trans-isomer
Relative standard deviation: NMT 2.0%
3.3 Analysis
Samples: Standard solution and Sample solution
Calculate the percentage of homosalate (C16H22O3 ) in the portion of Homosalate taken:
Result = (rU /rS )× (CS /CU) × 100
rU = sum of the peak responses for the cis- and trans-isomers from the Sample solution
rS = sum of the peak responses for the cis- and trans-isomers from the Standard solution
CS = concentration of USP Homosalate RS in the Standard solution (mg/mL)
CU = concentration of Homosalate in the Sample solution (mg/mL)
Acceptance criteria: 90.0%–110% on the as-is basis
4 SPECIFIC TESTS
Specific Gravity 〈841〉: 1.049–1.053
Refractive Index 〈831〉: 1.516–1.519 at 20°
5 ADDITIONAL REQUIREMENTS
Packaging and Storage: Preserve in tight containers.
USP Reference Standards 〈11〉
USP Homosalate RS
