USP Methods for the Analysis of Naproxen Using Legacy L1 Column

  Application Notes: Naproxen is a common NSAID used for pain relief and fever reducer. According to the USP methods, naproxen contains no less than 98% and no more than 101.5 percent naproxen calculated on a dried basis. The USP HPLC method for the separation of naproxen was developed on Legacy L1 column according to the US Pharmacopeia methodology. L1 classification is assigned to reversed-phase HPLC column containing C18 ligand. Support for the material is spherical silica gel with particles size 3-10 um and pore size of 100-120A. Resolution between critical pairs corresponds to rules and specifications of USP. Application Columns: Legacy L1 C18 HPLC column Application compounds: naproxen and benzophenone Mobile phase: water/MeCN/Glacial Acetic acid (49/50/1) Detection technique: UV Reference: USP35: NF30  


Column Legacy L1, 4.6x150 mm, 5 µm, 100A
Mobile Phase H2O/MeCN/Glacial Acetic acid (49/50/1)
Buffer Glacial Acetic acid
Flow Rate 1.0 ml/min
Detection UV, 254 nm


Class of Compounds Drug, Hydrophobic, Ionizable
Analyzing Compounds Naproxen, Benzophenone
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Application Analytes:
Naproxen Sodium

Application Detection:
UV Detection