title: Migration of copper from nanocopper/LDPE composite films.
abstract: Three nanocopper/low-density polyethylene (LDPE) composite films were tested in food simulants (3% acetic acid and 10% ethanol) and real food matrices (rice vinegar, bottled water and Chinese liquor) to explore the behaviours of copper migration using ICP-OES and GFAAS. The effects of exposure time, temperature, nanocopper concentration and contact media on the release of copper from nanocopper/LDPE composite films were studied. It was shown that the migration of copper into 10% ethanol was much less than that into 3% acetic acid at the same conditions. With the increase of nanocopper concentration, exposure time and temperature, the release of copper increased. Copper migration does not appear to be significant in the case of bottled water and Chinese liquor compared with rice vinegar with a maximum value of 0.54 μg mL-1for the CF-0.25# bags at 70°C for 2 h. The presence and morphology of copper nanoparticles in the films and the topographical changes of the films were confirmed by field emission scanning electron microscope (FE-SEM) and atomic force microscope (AFM). In this manner, copper nanoparticles of different morphologies, sizes and distribution were found, and samples with higher nanocopper concentration had a more irregular topography. In the case of Fourier transform infrared spectroscopy (FTIR), no chemical bonds formed between copper nanoparticles and LDPE. Copper nanoparticles were just as physically dispersed in LDPE.
authors.affiliation: a Department of Food Science and Engineering , Jinan University , Guangzhou , China.
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.affiliation: a Department of Food Science and Engineering , Jinan University , Guangzhou , China.|b Key Laboratory of Product Packaging and Logistics of Guangdong Higher Education Institutes , Jinan University , Zhuhai , China.
authors.forename: Chang-Ying
authors.initials: CY
authors.lastname: Hu
authors.affiliation: c Guangdong Inspection and Quarantine Technology Center , Guangzhou , China.
authors.forename: Quan
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: a Department of Food Science and Engineering , Jinan University , Guangzhou , China.
authors.forename: Yu-Jie
authors.initials: YJ
authors.lastname: Shi
authors.affiliation: c Guangdong Inspection and Quarantine Technology Center , Guangzhou , China.
authors.forename: Huai-Ning
authors.initials: HN
authors.lastname: Zhong
mesh_terms: D003300:Copper / Q000032:analysis*; D005504:Food Analysis; D005506:Food Contamination / Q000032:analysis*; D053768:Metal Nanoparticles / Q000737:chemistry*; D020959:Polyethylene / Q000737:chemistry
chemical_list: D003300:Copper; D020959:Polyethylene
keywords: AFM; FE-SEM; FTIR; GFAAS; ICP-OES; Nanocopper; composite film; food simulant; migration