We report the synthesis of monodisperse colloidal copper nanocrystals and subsequent solvent-dependent oxidation to form copper(I) oxide nanoparticles. The oxidation process was monitored by optical spectroscopy in the visible spectrum with the Cu nanocrystals exhibiting a surface plasmon feature that was replaced over time by an excitonic feature corresponding to the band gap of the Cu2O nanocrystals. The initial intensity of the copper plasmon was strongly dependent on the properties of the solvent used to form the nanocrystal dispersion; solvents with π-bonds significantly reduced (by >3-fold) the plasmon intensity and this effect was attributed to electron sharing between the solvent and the copper surface. The damped plasmon only recovered to its solvent-independent intensity once the nanocrystal surface oxidized and eliminated the solvent−Cu surface interactions. Solvents without π-bonds induced only a very small damping of the plasmon, and at longer time scales all solvents caused similar changes in the optical properties as oxidation converted the nanocrystals from metallic copper to semiconducting copper oxide.

We report a simple method to generate surface-anchored zwitterionic network coatings that exhibit low nonspecific protein adsorption. We first synthesize amphiphilic random copolymers comprising 2-(dimethylamino)­ethyl methacrylate (DMAEMA) and propargyl methacrylate (PGMA) units in two different nominal molar ratios (50:50 and 75:25) by free radical copolymerization. The DMAEMA moieties in the copolymers are then betainized with 1,3-propane sultone to obtain zwitterionic macromolecules. We create substrate-anchored network coatings by casting thin copolymer films (∼100 nm) containing 2 wt % of photoactive benzophenone onto a polystyrene substrate and cross-link them by UV-light irradiation at 365 nm (UV dose = 9–10 J/cm2). We investigate the cross-linking reaction with infrared spectroscopy, monitor the change in film thickness, and study the swelling behavior of the coatings as a function of ionic strength and electrolyte using spectroscopic ellipsometry. We demonstrate the performance of such surface-attached zwitterionic networks by studying their resistance to nonspecific adsorption of bovine serum albumin (BSA).