Enrico Stura

Gene expression in the cell cycle of human T-lymphocytes: II. Experimental determination by DNASER technology

Human lymphocytes gene expression before and after PHA stimulation is monitored by DNASER technology, a novel bioinstrumentation entirely constructed in our laboratories as previously reported. The validity of the DNASER measurements is confirmed by standard fluorescence microscopy equipped with CCD. The human lymphocytes gene expression here experimentally probed using commercially available DNA microarrays such as Human Starter, appears compatible both with independent bioinformatic prediction and with existing experimental data, pointing to MYC as the key gene in the G0–G1 transition induced by PHA in resting lymphocytes. It does not escape our notice that in cell biology and cancer research DNASER technology based on microarray constructed with few leader genes identified from bioinformatics represents a meaningful cost‐effective route alternative to massive frequently misleading molecular genomics. J. Cell. Biochem. 97: 1151–1159, 2006.

Atomic Force Microscopy and Anodic Porous Allumina of Nucleic Acid Programmable Protein Arrays

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.

Photoreversibility and photostability in films of octopus rhodopsin isolated from octopus photoreceptor membranes

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.

Optimization of Optical Properties of Polycarbonate Film with Thiol Gold-Nanoparticles

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.

Hybrid organic-inorganic electrolytic capacitors

Organic capacitors are among the most significant applications of conductive polymers, allowing the realization of lightweight and flexible dispositives. The main drawback of completely organic capacitors is the very low dielectric rigidity, due to irregular surface of the polymer-polymer interface. This paper describes our hybrid solution using aluminum electrodes, with the very important characteristic of easy connection between contacts of the discrete dispositive and electrodes. Chemical, technological, and functional tests have been conducted to estimate the effective values of this device, and natural properties of self-healing and nonpolarity have been investigated.

Polyaniline derivative nanocomposite materials for low power long life lithium batteries

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.

NEW NANOMATERIALS FOR LITHIUM BATTERY

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.