title: Monitoring of trace amounts of heavy metals in different food and water samples by flame atomic absorption spectrophotometer after preconcentration by amine-functionalized graphene nanosheet.
abstract: We are introducing graphene oxide modified with amine groups as a new solid phase for extraction of heavy metal ions including cadmium(II), copper(II), nickel(II), zinc(II), and lead(II). Effects of pH value, flow rates, type, concentration, and volume of the eluent, breakthrough volume, and the effect of potentially interfering ions were studied. Under optimized conditions, the extraction efficiency is >97 %, the limit of detections are 0.03, 0.05, 0.2, 0.1, and 1 μg L(-1) for the ions of cadmium, copper, nickel, zinc, and lead, respectively, and the adsorption capacities for these ions are 178, 142, 110, 125, and 210 mg g(-1). The amino-functionalized graphene oxide was characterized by thermogravimetric analysis, transmission electron microscopy, scanning electron microscopy, and Fourier transform infrared spectrometry. The proposed method was successfully applied in the analysis of environmental water and food samples. Good spiked recoveries over the range of 95.8-100.0 % were obtained. This work not only proposes a useful method for sample preconcentration but also reveals the great potential of modified graphene as an excellent sorbent material in analytical processes.
authors.affiliation: Department of Chemistry, Shahid Beheshti University, Evin, Tehran, Iran, mohammadbehbahani89@yahoo.com.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Behbahani
authors.forename: Nasim Akbari Ghareh
authors.initials: NA
authors.lastname: Tapeh
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Mahyari
authors.forename: Ali Reza
authors.initials: AR
authors.lastname: Pourali
authors.forename: Bahareh Golrokh
authors.initials: BG
authors.lastname: Amin
authors.forename: Ahmad
authors.initials: A
authors.lastname: Shaabani
mesh_terms: D002104:Cadmium / Q000032:analysis; D003300:Copper / Q000032:analysis; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000032:analysis*; D005504:Food Analysis / Q000379:methods; D005506:Food Contamination / Q000706:statistics & numerical data; D006108:Graphite / Q000737:chemistry; D019216:Metals, Heavy / Q000032:analysis*; D046529:Microscopy, Electron, Transmission; D009532:Nickel / Q000032:analysis; D052616:Solid Phase Extraction / Q000379:methods; D013054:Spectrophotometry, Atomic; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D004785:Environmental Pollutants; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D002104:Cadmium; D006108:Graphite; D003300:Copper; D009532:Nickel