title: Detection of the nanomolar level of total Cr[(iii) and (vi)] by functionalized gold nanoparticles and a smartphone with the assistance of theoretical calculation models.
abstract: We report a method for rapid, effective detection of both Cr(iii) and Cr(vi) (in the form of Cr(3+) and Cr2O7(2-), the main species of chromium in the natural environment) by making use of meso-2,3-dimercaptosuccinic acid (DMSA)-functionalized gold nanoparticles (Au NPs). The limit of detection (LOD) is 10 nM with the naked eye and the assay can be applied in detecting chromium in polluted soil from Yun-Nan Province in Southwest China. We use density functional theory to calculate the change of the Gibbs free energy (ΔG) of the interactions between the DMSA-Au NP system and various metal ions, which shows that DMSA-Au NPs have high specificity for both Cr(3+) and Cr2O7(2-).
authors.affiliation: Beijing Engineering Research Center for BioNanotechnology & Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, National Center for NanoScience and Technology, Beijing 100190, China. xingyujiang@nanoctr.cn wangz@nanoctr.cn.
authors.forename: Wenwen
authors.initials: W
authors.lastname: Chen
authors.forename: Fengjing
authors.initials: F
authors.lastname: Cao
authors.forename: Wenshu
authors.initials: W
authors.lastname: Zheng
authors.forename: Yue
authors.initials: Y
authors.lastname: Tian
authors.forename: Yunlei
authors.initials: Y
authors.lastname: Xianyu
authors.forename: Peng
authors.initials: P
authors.lastname: Xu
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Wang
authors.forename: Ke
authors.initials: K
authors.lastname: Deng
authors.forename: Xingyu
authors.initials: X
authors.lastname: Jiang
mesh_terms: D002857:Chromium / Q000032:analysis*; D006046:Gold / Q000737:chemistry; D007477:Ions / Q000737:chemistry; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D008670:Metals / Q000737:chemistry; D008962:Models, Theoretical; D000068997:Smartphone; D012989:Soil Pollutants / Q000032:analysis*; D013053:Spectrophotometry / Q000295:instrumentation; D004113:Succimer / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D007477:Ions; D008670:Metals; D012989:Soil Pollutants; D002857:Chromium; D006046:Gold; D004113:Succimer