Using the ring-shaped protein TRAP to capture and confine gold nanodots on a surface.

The cavity of the toroidal protein TRAP (trp RNA-binding attenuation protein) is modified to capture gold nanodots in solution. By engineering a titanium-binding peptide onto one surface of the ring it is also possible to bind it specifically and tightly to a TiO2 surface. TRAP bound in this way is then used to capture gold nanodots and attach them to prepared surfaces.

Surfactant gel adsorption of platinum(II), (IV) and palladium(II) as chloro-complexes and kinetic separation of palladium from platinum using EDTA.

A micellar solution of cetylpyridinium chloride (CPC) can separate into two phases due to a temperature change or to the addition of salts. Platinum(II), (IV) and palladium(II) reacted with chloride ions to form stable anionic complexes of PtCl4(2-), PtCl6(2-) and PdCl4(2-), respectively, and were adsorbed onto the CPC gel phase. The CPC phase plays the role of an ion-exchange adsorbent for the anionic complexes.

Ion-pair formation of a copper(II)-ammine complex with an anionic surfactant and the recovery of copper(II) from ammonia medium by the surfactant-gel extraction method.

The extraction and separation of copper(II), zinc(II), cobalt(II), and cadmium(II) were investigated. Both copper(II) and zinc(II) formed ammine-complexes, while cadmium(II) and cobalt(II) formed hydroxide precipitates in an ammonia medium. By the addition of sodium dodecylsulfate (SDS), a copper(II) complex formed an ion-pair (copper-ammine-DS), which was extracted into the SDS phase.

Preparation of ferrocyanide-imprinted pyridine-carrying microspheres by surface imprinting polymerization.

Ferrocyanide-imprinted pyridine-carrying microspheres were prepared using ferrocyanide ions as a template. This method is based on a surface imprinting technique from the seed emulsion that consisted of 4-vinylpyridine (functional monomer), styrene, and butyl acrylate and a water mixture polymerization by a radical initiator. The ferrocyanide-imprinted microspheres had about 200 times higher adsorption affinity over the non-imprinted microspheres in ferrocyanide (template) ion adsorption.