Determination of Diphenyl and o-Phenylphenol in Agricultural Products by GC/MS

Abstract

A simple determination method of diphenyl (DP) and o-phenylphenol (OPP) in agricultural products by GC/MS was examined. DP and OPP were extracted with ethyl acetate in the presence of anh. sodium sulfate. After addition of n-butanol, the extract solution was concentrated. Clean-up was achieved by shaking with graphitized bulk carbon (Supelclean ENVI-Carb). Addition of polyethylene glycol sharpened the OPP peak on GC/MS analysis.
The recoveries from 9 kinds of agricultural products spiked at 0.01 and 0.5 μg/g each were mostly in the range of 70 to 120%, except for 50% recovery of OPP from barley spiked at 0.01 μg/g. The quantification limits (S/N ≥10) of DP and OPP were 0.0013 and 0.005 μg/g (0.0025 and 0.01 μg/g in barley and soybean), respectively.