Determination of preservative parabens in oral and injection formulations by HPLC

Abstract

Two new HPLC-UV methods are described for determining methyl paraben and propyl paraben, methyl paraben sodium and propyl paraben sodium in oral and injection formulations. Separation of methyl paraben and propyl paraben, methyl paraben sodium and propyl paraben sodium by first method was effected by using an isocratic mobile phase of acetate buffer (pH = 4):methanol (18:82) on a 5 μm SGE C18 HQ 105 column (25 cm × 4.6 mm), the detector wavelength was set at 254 nm. Whereas the separation of methyl paraben and propyl paraben, methyl paraben sodium and propyl paraben sodium by second method was achieved by using mobile phase of acetate buffer (pH = 4):acetonitrile (20:80) on a 5μm SGE C18 HQ 105 column (25 cm × 4.6 mm), with UV detection at 254 nm. In both methods conditions, pump flow rate was 1 mL/min and sample injection volume 20 μL. Under these two methods conditions, separation of each two components was achieved in less than 6 min with a good resolution. Finally, these two HPLC methods are simple and quick for routine quantitative analysis of preservative parabens.