Study On The Determination Of Photo-initiators In Food Plastic Packaging And The Rule Of Migration

Plastic base package materials have become the main food packaging mate rials in food packaging industries,because they have extraordinary chemical stab ility,shaping,mechanical and copyright properties.But the safety of food plastic p ackaging materials has becoming an important concerning of food safety.The analysis of the residue of contaminations and the theory of migration are highli-ghted.Ultraviolet(UV)inks are widely used in food packaging materials becau se of its ex-cellent properties.Photoinitiators(PIs)are poisonous and irritantin,and they are also easy to volatilize and migrate.A simple and rapid analytical method was established for the determinatio n of 9 photo-initiators:Benzophenone(BP),2-MethylBenzophenone(2-MBP),1-Hydr oxycyclohexyl phenyl ketone(Irgacure 184),3-Methyl Benzophenone(3-MBP),4-Methyl Benzophenone(4-MBP),2,2-Dimethoxy-2-phenylacetophenone(Irgacure 651),o-Methyl-benzoyl Benzoate(OMBB),2-Ethylhexy-4-dimethylamion Benzoate(EHA)and 2-Isopropylthioxanthone(ITX)in the food plastic packaging by disp-ersive solid phase extraction(d-SPE)coupled with gas chromatography-mass s pectrometry(GC-MS).Photo-initiators were ultrasonically extracted by acetonitri le from samples,followed by concentrated under a stream nitrogen and then cl eaned up by the mixed sorbents of 150 mg anhydrous MgSO4,50 mg primary secondary amine(PSA)and 50 mg octadecylsilane(C18).The ultimate solutio n was detected by GC-MS with external standard method for quantitation unde r selected ion monitoring mode.All of the 9 photo-initiators had good linear r elationships in the concentrations of 0.02 to 1 mg/L,and the R2>0.999.The re coveries of 9 photo-initiators were in the range of 82.9%~118.9% at three spik e levels of 0.05,0.5 and 1mg/L,and the relative standard deviations(RSD)w ere 0.9%~10.5%(n=6).The limit of quantification(LOQ)for all analytes werera nge from 0.07 mg/kg to 0.33 mg/kg.The method was sample,good purificatio n effect,the sensitivity and precision meet the photo-initiator detection require ments,and it could be used for the determination of the residues of photo-initi ators in the food plastic packaging.The transfer phenomena between package materials and food simulant wer e also studied for the 7 PIs:2,2-Dimethoxy-2-phenylacetophenone(Irgacure 651),2-Ethylhexy-4-dimethylamionBenzoate(EHA),Benzophenone(BP),1-Hydroxycyclohexyl phenyl ketone(Irgacure 184),2-Isopropylthioxanthone(ITX),o-Methyl-benzoyl Benzoate(OMBB),Ethyl 4-dimethylaminobenzoate(EDB).The migration quantity affected by the migration time,the migration of PIs content increases with the number of days increase gradually,finally back into balance.The migration qu antity was affected by the block material,at the same concentration of the mix andthe food simulation conditions,the migration in different block material fo r PE>BOPP/CPP>BOPP/PET/CPPBOPP/LDPE>BOPP/LDPE.The migration quant ity affected by the mix standard concentration,the migration quantity of each PIs by mix standard concentration for 40 mg/L is double that of mix standard concentration of 20 mg/L.In addition,2-Ethylhexy-4-dimethylamion Benzoate(EHA)is not detected in different mix standard concentration and food simulant.The migration quantity of 2-Isopropylthioxanthone(ITX)is far less than o-Me thyl-benzoyl Benzoate(OMBB),Ethyl 4-dimethylaminobenzoate(EDB),1-Hydrox ycyclohexyl phenyl ketone(Irgacure 184),Benzophenone(BP),2,2-Dimethoxy-2-phenylacetophenone(Irgacure 651).In the same block material condition,the mig ration quantity of o-Methyl-benzoyl Benzoate(OMBB),Ethyl 4-dimethylaminob enzoate(EDB),1-Hydroxycyclohexyl phenyl ketone(Irgacure 184),Benzophenon e(BP),2-Isopropylthioxanthone(ITX)is the same in three kinds of food simula nt,but the migration quantity of 2,2-Dimethoxy-2-phenylacetophenone(Irgacure 651)in 3% acetic acid is far less than in Pure water and 10% ethanol.