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Updated: Aug 9, 2026

A Method for Selecting Structure-switching Aptamers Applied to a Colorimetric Gold Nanoparticle Assay
Published on: February 28, 2015
[Enrichment with polyamide and dual-wavelength spectrophotometric determination of gold and silver]
1Changchun Institute of Applied Chemistry, Academia Sinica, National Analytical Research Center of Electrochemistry and Spectroscopy, 130022 Changchun.
Abstract:
The absorbent performance of polyamide resin has been studied. Au(III) and Ag(I) easily react with [SCN]- to form complex anions in dilute nitric acid medium, and be adsorbed on the polyamide resin to enrich, and be separated from many other base metals. When Na2SO3 and NH3 x H2O is used as eluating agent, Au and Ag can be recovered quantitatively. Therein can be retreated and reused easily. In addition, we established a dual-wavelength spectrophotometric method which has been applied to the determination of Au(III) and Ag(I) in standard samples with relative standard deviation of less than 5.1%.
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