simultaneous determination of four preservatives in foodstuffs by high performance liquid chromatography

background and objectives:  high concentration of preservatives in food may result in gastrointestinal disturbances whereby some patients suffering from asthma, rhinitis, or urticaria. the aim of this study is the introduction and optimization a new method for simultaneous determination of four preservatives (sb, ps, mp, pp) in foodstuff by high performance liquid chromatography. materials and methods: important factors in extraction, separation and determination process were optimized using the one variable at a time method.  figures of merit of the proposed method were evaluated. the amount of sb, ps, mp, pp in some food samples were determined using the proposed method. result: the results showed that the obtained chromatogram of extract was free of significant interferences. the preservatives recoveries ranged from 88% to 110 %. concentration of sb, ps, mp and pp in the 20studied samples ranges between n.d-639.9, n.d -214.5, n.d -579.8 and n.d -30.5 mg kg-1, respectively  conclusion: the performance and reliability of proposed method as a simple, efficient and fast method for determination of sb, ps, mp, pp in the food samples was demonstrated.