| Popis: |
The sol–gel method is a straightforward technique that allows electrode modification with silica thin films. The silica pores could be functionalized to enhance the electrochemical and optical characteristics. Silica was functionalized with ferrocene using electroassisted accumulation, creating composite electrodes (Fc@Silica electrode). These electrodes were tested by electrochemical and spectroelectrochemical methods, showing that ferrocene was stably confined in silica. The Fc@Silica film enhances the electrochemical response of cytochrome c in solution, which gives rise to further applications and electrochemical studies of other redox-active proteins. Class I hybrid silica matrices were studied by adding negatively charged poly(4-styrene sulfonic acid) (PSS) and positively charged poly(diallyl dimethylammonium chloride) (PDADMAC) to the silica precursor solution. These hybrid films were functionalized with ferrocene species. Silica-PSS films showed higher ferrocenium cation accumulation capacity. UV-vis spectroscopy indicates the electroactivity of ferrocene confined within the silica and hybrid silica films. An enhancement in the cyt c signal was observed with the Fc@silica-PSS films. Silica was used as a host material for fluorescent conjugated polymers, specifically Poly(9,9-dioctyl-fluorene) (PFO). Polyfluorene nanoparticles were synthetized using the mini-emulsion method and were incorporated into a silica matrix. These matrices were used for the spectroelectrochemical detection of ferrocene. The reduced form of ferrocene quenches the fluorescence of PFO. The extent fluorescence quenching depends on the concentration of ferrocenium. Incorporating polyelectrolytes within silica enhanced the performance of the spectroelectrochemical sensor. PFO@silica-PSS shows an improved response to ferrocene, offering new opportunity for the spectroelectrochemical detection of other redox species. |
