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entation of alkanethiol-coated gold nanowires (containing a short nickel segment) between horizontal and verticalpositions to allow the transducer to perform the measurement and reset it to the protection mode betweensuccessive measurements. This leads to "opening" and "closing" of the surface and hence switching between active(sensing) and passive (protection) modes. Such on-demand protection and minimization of surface-foulingare indicated from prolonged series of stripping-voltammetric measurements of cadmium in the presence of gelatin,albumin, or Tween80. Factors influencing the protective action of the adaptive nanowires, including thelength of the alkanethiol layer or of the gold/nickel segments were examined and optimized. Such on-demandprotection capability should facilitate practical sensing applications of electrochemical devices.2. Bulbarello, S. Sattayasamitsathit, A. G. Crevillen, J. Burdick, S. Mannino, P. Kanatharana, P.Thavarungkul, A. Escarpa, J. Wang. (2009) Striped Alloy Nanowire Optical ReflectanceBarcodes Prepared from a Single Plating Solution / A, Small. - 4:5 - p. 597-600.2. Granato F., Scampicchio M., Bianco A., Mannino S., Bertarelli C., Zerbi G. (2008)Disposable electrospun electrodes based on conducting nanofibers. Electroanalysis 20:1374-1377A new approach for the fabrication of disposable electrochemical surfaces is presented. Conducting fibers havebeen produced by a two-step process. Firstly, a fine web mat composed of nylon-6 and ferric chloride fibers(with diameters of about 200 nm) were electrospun on a flat collector. Afterwards, the electrospun mat was exposedto pyrrole vapor under controlled dry atmosphere until each nylon thread was fully coated with a conductingpolypyrrole layer. The conducting fiber mat was finally integrated within an electrochemical cell and used asa disposable sensor device. The suitability of the sensor was tested using phosphate and carbonate organic anions.The large scale fabrication of conducting tissue, in the form of a fine web of spun nanofibers, is relativelyfast and inexpensive, and it paves the way to the build up of new disposable electrodes.3. Scampicchio M., Bulbarello A., Arecchi A., Mannino S. (2008) Electrospun nanofibers as selectivebarrier to the electrochemical polyphenol oxidation. Electrochemistry Communications10: 991-994.A tissue made of nylon-6 electrospun nanofibers has been fabricated and placed over a glassy carbon electrode.The resulting coating eliminates the passivation effect of the electrode surface caused by polyphenols oxidation,while the characteristic waves of small biological antioxidants are not affected.4. Wang J, Scampicchio M, Laocharoensuk R, Valentini F, Gonzalez-Garcia O, Burdick J.(2006) Magnetic tuning of the electrochemical reactivity through controlled surface orientationof catalytic nanowires, Journal Of The American Chemical Society 128: 4562-4563Nanowires have received considerable attention owing to their broad potential applications. We report here onthe application of nanowires for magnetic control of the electrochemical reactivity and demonstrate how one canmodulate the electrocatalytic activity by orienting catalytic nanowires at different angles. Unlike early “on/off”magnetic switching studies based on functionalized magnetic spheres, the present magnetoswitchable protocolrelies on modulating the electrochemical reactivity without removing the magnetic material from the surface.Such behavior is attributed to the reversible blocking of the redox processes and to changes in the tortuositydependentflux rate. The nanowire-based magnetoswitchable protocol may be extremely useful for adjusting theelectrochemical reactivity, such as for tuning the power output of fuel cells (rather than switching the poweron/off).5. Scampicchio M, Wang J, Blasco AJ, Arribas AS, Mannino S, Escarpa A, (2006) Nanoparticle-basedassays of antioxidant activity, Analytical Chemistry 78: 2060-2063The antioxidant power of several phenolic acids and related food samples is estimated from the generation andgrowth of gold nanoparticles. The intensity of the resulting particle plasmon absorption bands correlates wellwith the redox characteristics of these phenolic acids estimated from cyclic voltammetry experiments. The highestcapacity of reducing gold(III) to gold nanoparticles corresponds to the highest antioxidant activity, consistentwith the tendency of phenolic acids to donate electrons.SISTAL - SOCIETA’ ITALIANA DI SCIENZE E TECNOLOGIE ALIMENTARIDipartimento di Scienze e Tecnologie Agroalimentari, Università degli Studi della TusciaVia San Camillo de Lellis, 01100 ViterboTel.: 0761- 35 74 94/7 , Fax: 0761- 35 74 98, e-mail: mmoresi@unitus.it202