|Molecular Weight||252.245 g/mol|
Mixed-mode columns allow to quantitate drugs and their counter-ions in one run. Hydrophobic acidic drug and hydrophilic inorganic counter-ions are separated and quantified on an Obelisc R HPLC trimodal column. This column can be used to quantify hydrophilic basic and hydrophilic acidic drugs, hydrophobic basic and hydrophobic acidic drugs, and corresponding organic and inorganic counter-ions. Various detection techniques can be applied to obtain reliable and robust method. Mixed-mode chromatography allows to retain ionizable compounds without ion-pairing reagent. This HPLC method can be adopted as universal and robust approach for analysis basic and acidic drugs and their counter-ions. Method is compatible with various detection techniques - ELSD, UV, CAD, and LC/MS.
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 bezophenone
Mobile phase: water/MeCN/Glacial Acetic acid (49/50/1)
Detection technique: UV
Reference: USP35: NF30