Organo-soluble photoresponsive azo thiol monolayer-protected gold nanorods.

Organo-soluble photoresponsive azo thiol monolayer-protected gold nanorods were synthesized; the resulting gold nanorods encapsulated by thiols on their entire surface with strong covalent Au-S linkages were very stable in both organic solvents and in the solid state without aggregation or decomposition.

A facile synthesis of aliphatic thiol surfactant with tunable length as a stabilizer of gold nanoparticles in organic solvents.

Three new aliphatic thiol surfactants were synthesized by reacting alkyl bromide with hexamethyldisilathiane under a mild condition. This approach provides an easy access for the direct synthesis of various different length thiol surfactants which play a crucial role in tuning the properties of gold nanoparticles. Gold nanoparticles encapsulated with one of our synthetic thiols were prepared and well characterized by H NMR, UV-vis, FT-IR, and TEM.

A colorimetric titration method for quantification of millimolar glucose in a pH 7.4 aqueous phosphate buffer.

3-Pyridinylboronic acid is identified as a key sensing element for reversible sugar complexation in an aqueous solution at the physiological pH. The utility of a sensing element has been demonstrated through a simple colorimetric titration of glucose using absorption spectroscopy in the visible region. The mechanism of the high diol/triol binding affinity of pyridine boronic acid in the neutral pH is discussed based on the 1H and 11B NMR spectroscopic studies.

Photochemical patterning of a self-assembled monolayer of 7-diazomethylcarbonyl-2,4,9-trithiaadmantane on gold films via Wolff rearrangement.

Photolithographic attachment of functional organic molecules via ester or amide linkages to self-assembled monolayers (SAMs) on gold thin films was achieved by employing a novel photoreactive surface anchor, 7-diazomethylcarbonyl-2,4,9-trithiaadmantane. The photoreactive SAM was prepared by the spontaneous physical adsorption of the photoreactive surface anchor onto gold surfaces. The alpha-diazo ketone moiety of the SAM was found to display the classical Wolff rearrangement reactivity to produce a ketene intermediate on the exposed area.