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A new nanostructured composite film based on thiol gold nanoparticles dispersed in polycarbonate and prepared by evaporating a solution of 1-dodecanthiol gold nanoparticles and polycarbonate was developed for applications as optical lenses. Lenses with superior mechanical properties, coloring and UV ray absorption and with the same transparency as the matrix were obtained. The supporting highly transparent polycarbonate matrix and the chloroform solution of thiol gold nanoparticles, 3 nm mean size, was mixed according to a doping protocol employing different concentrations of thiol gold nanoparticles vs. polycarbonate. The presence of nanoparticles in the polymer films was confirmed by the spectrophotometric detection of the characteristic absorbance marker peak at 540–580 nm. The nanostructured films obtained show a better coverage in the UV-vis range (250–450 nm) even at very low doping ratios, of the order of 1:1,000. These results offer a very promising approach towards the development of efficient nanostructured materials for applications to optical lenses.

This paper describes a nanoporous substrate for applications in biomedical diagnostics. A photolithographic microstructuring technique for an ordered nanopore array fabrication is reported. The process uses a negative resist with hydrophobic properties increasing specificity to biomolecule linking. Nanoporous alumina is formed by an anodic process and yields straight holes with high aspect ratio: its use as substrates for DNA-microarray or protein-chip application offers several advantages over conventional supports, making them very attractive to use as supports for biological sample microarray application.

Nanocomposite materials of poly(o-anisidine) (POAS) containing titanium dioxide nanoparticles (TiO2), carbon black (CB) and multi-walled carbon nanotubes (MWNT) were prepared. The synthesized materials were deposited in thin films in order to investigate their impedance characteristics by comparison. Electrochemical impedance spectroscopy (EIS) study was performed using the prepared films as working electrodes in a three electrodes configuration cell. Comparison between the fitting parameters was carried out in order to identify the improved nanocomposite for biosensor applications.

Recently, nanotechnology has entered the fields of sensors and biosensors. Of particular interest is how sensitivity, selectivity, and switching may be improved by directly contacting single molecules. To achieve this goal, the fabrication of electrodes separated by nanometric size gaps that may be bridged by single molecules is necessary. Two approaches to fabricate nanometric sized contacts were recently proposed in literature. The first involves the movement of electrodes pairs. The second relates to the formation of electrodes pairs via etching. The aim of this work is to review techniques of fabricating nanometer scale gaps between conducting materials, used to form nanocontacts to single molecules.

A nanocomposite of multiwalled carbon nanotubes (MWNTs) embedded in poly(2,5-dimethylaniline) (PDMA) was synthesised by oxidative polymerisation. The nanocomposite (PDMA–MWNTs) showed a progressive spontaneous undoping process along the time associated to the instability of the doping agent, constituted by HCl, inside the polymeric matrix. The study of the undoping process revealed that this phenomenon is related to the synergetic effect of the sterical hindrance of the substituents on the aromatic rings and the presence of MWNTs inside the polymeric matrix. The conducting properties connected to a doping–undoping equilibrium in the presence of the doping agent were also investigated. The instability of the doping process allowed us to fabricate a spontaneous reversible sensor for acid vapours by setting up a comparative potentiometric circuit and engineering the sensitive element directly on the circuit board.

The methodological aspects are here presented for the NAPPA (Nucleic Acid Programmable Protein Arrays) characterization by atomic force microscopy and anodic porous alumina. Anodic Porous Alumina represents also an advanced on chip laboratory for gene expression contained in an engineered plasmid vector. The results obtained with CdK2, CDKN1A, p53 and Jun test genes expressed on NAPPA and the future developments are discussed in terms of our pertinent and recent Patents and of their possibility to overcome some limitations of present fluorescence detection in probing protein-protein interaction in both basic sciences and clinical studies.

In this work, a new biomaterial resulting from the isolation of octopus rhodopsin (OR) starting from octopus photoreceptor membranes is presented. Mass spectroscopic characterization was employed in order to verify the presence of rhodopsin in the extract. Photoreversibility and photochromic properties were investigated using spectrophotometric measurements and pulsed light. Thin films of OR were realized using the gel-matrix entrapment method in polyvinyl alcohol solution. The results indicate that the photoreversibility and the photostability of the OR in gel-matrices are maintained. Several measurements were performed to test the stability of the resulting biomaterial in time and at room temperature. Preliminary tests demonstrate that the photoreversibility and the photostability are still found after few days from the biomaterial preparation and after the exposure for several hours at room temperature.

In this work, to improve the mechanical stability of electrodes based on P450scc for LDL-cholesterol detection and measure, anodic porous alumina (APA) was used. This inorganic matrix, which pores can be tuned in diameter modifying the synthesis parameters, was realized with cavities 275 nm wide and 160 μm deep (as demonstrated with AFM and SEM measurement), to allow the immobilization of P450scc macromolecules preserving their electronic sensitivity to its native substrate, cholesterol. Even if the sensitivity of the APA + P450scc system was slightly reduced with respect to the pure P450scc system, the readout was stable for a much longer period of time, and the measures remained reproducible inside a proper confidentiality band, as demonstrated with several cyclic voltammetry measures. To optimize the adhesion of P450scc to APA, a layer of poly- l -lysine, a poly-cathion, was successfully implemented as intermediate organic structure.

Electronic portable devices requir e power source providing sufficient energy for a long time of service. Rechargeable batteries are often used, and recently most of the industries choose lithium – polymer systems. Many materials were tested for each part of the battery, anode, cathode and electrolyte. Our goal is to develop an organic polymeric material to be used as cathode. Two very important characteristics of a portable power supply are the energy storage / weight and energy storage / volume ratio, since the constant electronics evoluti on is leading to light circuits with very small dimensions. Conjugated conducting polymers has been widely studied for electronic uses, then we chose a low cost polyaniline derivative, poly(ortho -anisidine), because of its better chemical properties of sol ubility with respect to normal polyaniline. During the synthesis, titanium dioxide (TiO 2) particles were added, since in our previous works was demonstrated that this procedure improved the storage characteristics of the material with respect to the pure p olymer. To inspect the electrochemical properties of the material, cyclic voltammetry was performed by using directly the electrolytic cell with traditional lithium – polymer elements: lithium foil as anode, liquid electroyte (LP30, 1 M solution of LiPF 6 in ethylene carbonate : dimethyl carbonate 1:1) pregnating a soft and porous inert material. Intercalation of Li + ion was studied basing on these voltammograms. Repetitive charge / discharge test were conducted in order to verify the long term cyclability o f the realized dispositives, and after a 50 cycle analysis it was noticed that the 60% of the initial capacity was preserved. The investigated material showed good performance in low current experiments, both for the charge and the discharge process. Capac ity values of the realized electrolytic cells tend to decrease as the flowing current increases.

A gas sensor, fabricated by selective growth of aligned carbon nanotubes (CNTs) by pulsed plasma on Si 3 N 4 /Si substrates patterned by metallic platinum, is presented for inorganic vapor detection at room temperature. Poly( o -anisidine) (POAS) deposition onto the CNTs device was shown to impart higher sensitivity to the sensor. Upon exposure to HCl the variation of the CNTs sensitivity is less than 4%, while the POAS-coated CNTs devices offer a higher sensitivity (i.e. 28%). The extended detection capability to inorganic vapors is attributed to direct charge transfer with electron hopping effects on intertube conductivity through physically adsorbed POAS between CNTs.

Composite nanomaterials of poly(o-anisidine) (POAS) with nanomaterials TiO2, carbon black and carbon nanotubes were prepared. The synthesized nanomaterials were deposited in thin films in order to fabricate the cathodes. The electrochemical impedance spectroscopy (EIS) was performed using the prepared cathodes as working electrodes in a three electrodes configuration. The impedance behavior of these cathodes was analyzed in order to estimate the electrochemical parameters of the novel materials. A comparison between the fitting parameters were carried out in order to focus the future research on improved nanocomposite. The data obtained is discussed with reference to the development of improved nanocomposites for cathodes in lithium battery.