Ciprofloxacin was the first fluoroquinolone brought to the market, in 1987, and represented an important medical breakthrough driving further research into this new class of antibiotics. It was developed in 1981 by Bayer and is currently the most potent of available fluoroquinolones. A broad-spectrum antibiotic it is used to treat several bacterial infections. Literature citations reference the use of a C18 HPLC column. However, due to the aromatic functionality with ciprofloxacin it makes it an ideal candidate for the application of a phenyl based stationary phase. This application brief describes use of a Quasar biphenyl column in the analysis of the synthetic antibiotic ciprofloxacin.