Determination of Sildenafil Citrate Illegally Mixed into Jinsuo Gujing Pills by LC-MS

OBJECTIVE To detect sildenafil citrate illegally mixed into Jinsuo Gujing pills by LC-MS. METHODS The sildenafil citrate of Jinsuo Gujing pills was analyzed through a C₁₈ column (2.1 mm×100 mm, 5 µm), using the mobile phase of acetonitrile-0.01 mol·L^-1 ammonium acetate by gradient elution. RESULTS Sildenafil citrate were found in the drugs. CONCLUSION The method is simple, sensitive and accurate. It can be used to detect sildenafil citrate mixed into illegal drug.