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.

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-).

[1]  D. Bagchi,et al.  Cytotoxicity and oxidative mechanisms of different forms of chromium. , 2002, Toxicology.

[2]  Xingyu Jiang,et al.  Recent progress in the application of microfluidic systems and gold nanoparticles in immunoassays , 2011 .

[3]  J. Wise,et al.  Carcinogenicity of hexavalent chromium. , 2008, The Indian journal of medical research.

[4]  K. Janardhanam,et al.  Speciation determination of chromium(III) and (VI) using preconcentration cloud point extraction with flame atomic absorption spectrometry (FAAS). , 2008, Journal of hazardous materials.

[5]  Wei Zhang,et al.  Highly sensitive, colorimetric detection of mercury(II) in aqueous media by quaternary ammonium group-capped gold nanoparticles at room temperature. , 2010, Analytical chemistry.

[6]  Xingyu Jiang,et al.  Gold nanoparticles for the colorimetric and fluorescent detection of ions and small organic molecules. , 2011, Nanoscale.

[7]  Jiashu Sun,et al.  An ultrasensitive, non-enzymatic glucose assay via gold nanorod-assisted generation of silver nanoparticles. , 2013, Nanoscale.

[8]  Jiashu Sun,et al.  A Highly Sensitive Gold‐Nanoparticle‐Based Assay for Acetylcholinesterase in Cerebrospinal Fluid of Transgenic Mice with Alzheimer's Disease , 2012, Advanced healthcare materials.

[9]  A. Zhitkovich.  Importance of chromium-DNA adducts in mutagenicity and toxicity of chromium(VI). , 2005, Chemical research in toxicology.

[10]  Max Costa,et al.  Toxicity and Carcinogenicity of Chromium Compounds in Humans , 2006 .

[11]  D. Bagchi,et al.  Comparing metabolic effects of six different commercial trivalent chromium compounds. , 2008, Journal of inorganic biochemistry.

[12]  Shih-Ming Yang,et al.  Simultaneous determination of chromium(III) and chromium (VI) with reversed-phase ion-pair high-performance liquid chromatography , 1993 .

[13]  P. Tchounwou,et al.  Oxidative stress, DNA damage, and antioxidant enzyme activity induced by hexavalent chromium in Sprague‐Dawley rats , 2009, Environmental toxicology.

[14]  Xingyu Jiang,et al.  A highly sensitive, dual-readout assay based on gold nanoparticles for organophosphorus and carbamate pesticides. , 2012, Analytical chemistry.

[15]  Chunhai Fan,et al.  Catalytic gold nanoparticles for nanoplasmonic detection of DNA hybridization. , 2011, Angewandte Chemie.

[16]  Sadia Afrin Khan,et al.  Multifunctional oval-shaped gold-nanoparticle-based selective detection of breast cancer cells using simple colorimetric and highly sensitive two-photon scattering assay. , 2010, ACS nano.

[17]  David K. Liu,et al.  Chromium and hexavalent chromium , 1993, Journal of applied toxicology : JAT.

[18]  Y. Negishi,et al.  One-pot preparation of subnanometer-sized gold clusters via reduction and stabilization by meso-2,3-dimercaptosuccinic acid. , 2003, Journal of the American Chemical Society.

[19]  Xianxiang Wang,et al.  Colorimetric speciation of Cr(III) and Cr(VI) with a gold nanoparticle probe , 2013 .

[20]  X. Shan,et al.  Separation of Cr(III) and Cr(VI) in river and reservoir water with 8-hydroxyquinoline immobilized polyacrylonitrile fiber for determination by inductively coupled plasma mass spectrometry. , 2002, Talanta.

[21]  A. Menegário,et al.  On-line preconcentration and speciation analysis of Cr(III) and Cr(VI) using baker's yeast cells immobilised on controlled pore glass , 2005 .

[22]  W. Mertz.  Chromium in human nutrition: a review. , 1993, The Journal of nutrition.

[23]  K. Wrobel,et al.  Effect of chromium on glucose tolerance, serum cholesterol and triglyceride levels in occupational exposure to trivalent species in type 2 diabetic patients and in control subjects , 1999 .

[24]  W. Tseng,et al.  Role of 5-thio-(2-nitrobenzoic acid)-capped gold nanoparticles in the sensing of chromium(vi): remover and sensor. , 2011, The Analyst.

[25]  Hai Shen,et al.  Bacterial reduction of hexavalent chromium , 1995, Journal of Industrial Microbiology.

[26]  Scott Fendorf,et al.  Genesis of hexavalent chromium from natural sources in soil and groundwater , 2007, Proceedings of the National Academy of Sciences.

[27]  B. Delley.  An all‐electron numerical method for solving the local density functional for polyatomic molecules , 1990 .

[28]  Wang,et al.  Accurate and simple analytic representation of the electron-gas correlation energy. , 1992, Physical review. B, Condensed matter.

[29]  G. Shi,et al.  A Simple and Sensitive Method for the Amperometric Detection of Trace Chromium(VI) Based on Prussian Blue Modified Glassy Carbon Electrode , 2009 .

[30]  W. Glinsmann,et al.  Effect of trivalent chromium on glucose tolerance. , 1966, Metabolism: clinical and experimental.

[31]  Hong-Wei Li,et al.  Selective detection of trace Cr3+ in aqueous solution by using 5,5'-dithiobis (2-nitrobenzoic acid)-modified gold nanoparticles. , 2009, ACS applied materials & interfaces.

[32]  A. Becke.  A multicenter numerical integration scheme for polyatomic molecules , 1988 .

[33]  Ping Yu,et al.  Competitive coordination of Cu2+ between cysteine and pyrophosphate ion: toward sensitive and selective sensing of pyrophosphate ion in synovial fluid of arthritis patients. , 2013, Analytical chemistry.

[34]  A. Zhitkovich.  Chromium in Drinking Water: Sources, Metabolism, and Cancer Risks , 2011, Chemical research in toxicology.

[35]  B. Goldstein,et al.  Enhancement of post‐receptor insulin signaling by trivalent chromium in hepatoma cells is associated with differential inhibition of specific protein‐tyrosine phosphatases , 2001 .

[36]  X. Quan,et al.  Selective detection of nanomolar in aqueous solution based on functionalized gold nanoparticles. , 2011, Analytical methods : advancing methods and applications.

[37]  Y. Tong,et al.  Spectroscopic evidence of a bidentate-binding of meso-2,3-dimercaptosuccinic acid on silver nanoclusters , 2011 .