A simultaneous determination method for diphenyl(DP)and ortho-phenylphenol(OPP)in citrus fruits, by high performance liquid chromatography(HPLC), was examined. Control and imported fruits were used. For two hrs twice DP and OPP were extracted, by reflux distillation with water, into cyclohexane. HPLC analysis was carried out with Finepak SIL <special>C18-T</special> as packing materials, dilute methanol as mobile phase, and ultraviolet detector at 254nm. The quantitative exactitude of HPLC was confirmed by comparing chromatograms of control fruits with those of contaminated ones. The recovery rates, after adding two preservatives from the control fruits by this method, were 96.7-101.8% for DP after 2 hrs' distillation and 90.5-102.5% for OPP after 4 hrs' distillation. This method has the advantages of simple extraction procedure, lesser solvent consumption, and adequate accuracy. The minimum concentration for determination by this method is 0.1μg DP or OPP per g sample.
The Determination of Diphenyl and ortho-Phenylphenol in Citrus Fruits by High Performance Liquid Chromatography
