Scanning electrochemical microscopy. 24. Enzyme ultramicroelectrodes for the measurement of hydrogen peroxide at surfaces.
نویسندگان
چکیده
Hydrogen peroxide sensing microelectrodes for scanning electrochemical microscopy (SECM) have been developed and used to measure hydrogen peroxide in the diffusion layer during electrochemical reduction of oxygen on gold and carbon electrodes. These microelectrode biosensors were also used to detect immobilized glucose oxidase through the production of hydrogen peroxide during enzymatic oxidation of glucose. Images of hydrogen peroxide concentration profiles near a platinum microdisk during catalytic decomposition of peroxide and in the diffusion layer of a carbon-platinum composite electrode during oxygen reduction are presented. The factors limiting the spatial resolution (tens of micrometers) and potential applications of the technique are discussed.
منابع مشابه
Fabricating and imaging carbon-fiber immobilized enzyme ultramicroelectrodes with scanning electrochemical microscopy.
The scanning electrochemical microscope (SECM) is used to image the activity of enzymes immobilized on the surfaces of disk-shaped carbon-fiber electrodes. SECM was used to map the concentration of enzymatically produced hydroquinone or hydrogen peroxide at the surface of a 33-microm diameter disk-shaped carbon-fiber electrode modified by an immobilized glucose-oxidase layer. Sub-monolayer cove...
متن کاملUltramicrosensors based on transition metal hexacyanoferrates for scanning electrochemical microscopy
We report here a way for improving the stability of ultramicroelectrodes (UME) based on hexacyanoferrate-modified metals for the detection of hydrogen peroxide. The most stable sensors were obtained by electrochemical deposition of six layers of hexacyanoferrates (HCF), more specifically, an alternating pattern of three layers of Prussian Blue and three layers of Ni-HCF. The microelectrodes mod...
متن کاملBipolar electrochemical mechanism for the propulsion of catalytic nanomotors in hydrogen peroxide solutions.
Bimetallic nanorods are propelled in aqueous solutions by the catalytic decomposition of hydrogen peroxide to oxygen and water. Several mechanisms (interfacial tension gradients, bubble recoil, viscous Brownian ratchet, self-electrophoresis) have been proposed for the transduction of chemical to mechanical energy in this system. From Tafel plots of anodic and cathodic hydrogen peroxide reaction...
متن کاملA printed electrocatalyst for hydrogen peroxide reduction
The modification of silver screen-printed electrodes with a dodecyl benzenesulphonic acid and KCl solution was performed by inkjet printing. Scanning Electron Microscopy was performed to characterize the electrode surfaces. Electrochemical reduction of H2O2 was studied and compared to electrodes modified by dip-coating. Analytical parameters of the allprinted electrode such as LOD, sensitivity ...
متن کاملScanning electrochemical microscopy, 52. Bipolar conductance technique at ultramicroelectrodes for resistance measurements.
The bipolar conductance, BICON, technique for the measurement of solution resistance, based on the application of microsecond current pulses, as originally described by Enke and co-workers for measurements with conventional electrodes, was extended for use with ultramicroelectrodes, with a focus on its application in scanning electrochemical microscopy (SECM). When the plateau time used to make...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Analytical chemistry
دوره 65 24 شماره
صفحات -
تاریخ انتشار 1993