title: Graphene sheet-starch platform based on the groove recognition for the sensitive and highly selective determination of iodide in seafood samples.
abstract: The functionalization of graphene nanosheets was realized using a simple starch mixture to achieve a highly selective recognition of iodide, thereby surmounting the complicated reactions possibly leading to low yield during functionalization. The groove recognition for starch to iodide, a novel recognition model, was established. The starch-to-graphene nanosheet mass ratio of 3:2 produced an optimal current signal. The recognition and measurement procedures were conducted in different cells, respectively. These procedures improved the selectivity and sensitivity, and overcame the possibility of interference from coexisting ions. Under optimal conditions, the graphene sheet-starch electrode was immersed in a recognition cell at pH 2.0 for 10min, afterward, in a measurement cell at pH 1.0 for quantitative analysis, resulting in the highest current signals obtained. The quantitative electrochemical measurements yielded a mean value of 214.6mg/kg in actual samples of commercially available seafood sample, whereas the spectrophotometric measurements produced a mean value of 226.7mg/kg. If the spectrophotometric value for the seafood sample is accurate, the percentage error for the electrochemical method is only 5.3%. Therefore, the electrochemical method is reliable for qualitative iodide measurements. The groove recognition was highlighted to elucidate the specific selectivity.
authors.affiliation: College of Chemistry and Bioengineering, Jiangsu Key Laboratory for Environmental Functional Materials, Suzhou University of Science and Technology, Suzhou 215009, China. shouqingliu@hotmail.com
authors.forename: Shou-Qing
authors.initials: SQ
authors.lastname: Liu
authors.forename: Feng-Tian
authors.initials: FT
authors.lastname: Hu
authors.forename: Cheng-Bao
authors.initials: CB
authors.lastname: Liu
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.forename: Zheng-Ying
authors.initials: ZY
authors.lastname: Wu
authors.forename: Zuo-Qin
authors.initials: ZQ
authors.lastname: Liang
authors.forename: Nan
authors.initials: N
authors.lastname: Xu
authors.forename: Zhi-Gang
authors.initials: ZG
authors.lastname: Chen
mesh_terms: D015374:Biosensing Techniques; D055664:Electrochemical Techniques; D005504:Food Analysis; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D007454:Iodides / Q000302:isolation & purification*; D017747:Seafood / Q000032:analysis; D013213:Starch / Q000737:chemistry*
chemical_list: D007454:Iodides; D006108:Graphite; D013213:Starch