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《中国化学快报》2019,30(9):1659-1662
The development of efficient methods for the detection of hazardous and toxic elements is extremely important for environmental security and public health. In this work, we developed a facile colorimetric assaying system for Ag+ detection in aqueous solution. Chitosan-stabilized platinum nanoparticles (Ch-PtNPs) were synthesized and severed as an artificial oxidase to catalyze the oxidation of the substrate 3,3′,5,5′-tetramethylbenzidine (TMB) and generate color signal. In the presence of Ag+, due to the strong metallophilic interactions between Ag+ and Pt2+ on the surface of Ch-PtNPs, Ag+ can weaken the affinity to the substrates and inactivate the catalytic activity of Ch-PtNPs, leading to decreased absorbance signal to varying degrees depending on Ag+ amount. Combing the specific binding between Ch-PtNPs and Ag+ with signal amplification procedure based on the Ch-PtNPs-catalyzed TMB oxidation, a sensitive, selective, simple, cost-effective, and rapid detection method for Ag+ can be realized. Ag+ ions in tap and lake waters have been successfully detected. We ensured that the proposed method can be a potential alternative for Ag+ determination in environmental samples. 相似文献
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Ana M. Costero Joaquín Sanchis Salvador Gil Vicente Sanz M. Carmen Ramírez De Arellano J.A. Gareth Williams † 《Supramolecular chemistry》2013,25(6):435-446
Eight new polyazapodands containing a 4,4′-substituted biphenyl moiety have been synthesised. Four (7, 8, 9 and 11) are functionalised on positions 4 and 4′ with a nitro group and four (1, 2, 3 and 10) with a dimethylamino substituent. Comparison of the emission behaviour of 1, 2, 3 with that of the reference compounds 10 and tetramthylbenzidine, clearly suggests that a modification in the dihedral angle between the biphenyl rings is an important factor in determining the fluorescent response of the molecule. The fluorescence is pH dependent, due to the formation of intramolecular hydrogen bonds between protonated aliphatic nitrogens and a carbonyl oxygen, which influences the aforementioned dihedral angle. A crystal structure resolved by X-ray diffraction of 7·2HCl has been determined, and confirms the dependence of the angle and the rigidity on the hydrogen bonding. The complexation properties of these ligands have been studied with Zn2+, Cd2+, Ni2+, Cu2+ and Pb2+, which show that the number of amino groups within the pendants has a strong influence on the nature of the complexation and the fluorescent response of each ligand. 相似文献
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A glassy carbon electrode modified with carbon nanotube and bimetallic inorganic‐organic nanofiber hybrid nanocomposite was prepared and used for determination of trace levels of guaifenesin. A modified glassy carbon electrode was developed for the rapid, selective, sensitive and low cost monitoring of guaifenesin. Oxidation of guaifenesin on the surface of the modified electrode was investigated with differential pulse voltammetry and the results showed that the modified electrode remarkably improved sensitivity and selectivity for the electrochemical assay of guaifenesin. Detection limit and quantitation limit were found to be 0.0175 µM and 0.0583 µM, respectively. 相似文献
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Haohua Deng Shaobin He Xiuling Lin Lu Yang Zhen Lin Ruiting Chen Huaping Peng Wei Chen 《中国化学快报》1990,30(9):1659-1662
A facile colorimetric method for sensitive and selective detection of Ag+ is successfully developed based on the excellent oxidase-like activity of chitosan-stabilized platinum nanoparticles and the strong metallophilic Pt2+-Ag+ interactions. 相似文献
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