Biologically friendly room temperature ionic liquids and nanomaterials for the development of innovative enzymatic biosensors.

Main purpose of the work is assembling, testing and optimizing new disposable amperometric biosensors to analyze substances in different application fields as agribusiness, clinical chemistry and environment protection. Many kinds of modified electrodes have been prepared and tested to build portable devices to analyze quickly many analytes, in a simple and cost-effective manner. Bare electrodes of the screen-printed type, with silver as reference, have been used for modification. The glassy carbon electrodes with multi-walled carbon nanotubes or graphene or gold nanoparticles depositions were modified with generation IV ionic liquids. Choline as cation and amino acids, such as glycine, serine, phenylalanine and histidine, as anions have been employed for these ionic liquids. The presence of nanostructured materials on the electrode brings an increased contact surface between analytes and receptor and, consequently, an amplification of the amperometric signal and a better sensibility. Moreover the use of new ionic liquids of generation IV, biologically friendly and water soluble, improves the electronic transfer, facilitating and strengthening the redox reaction nearby the electrode. By immobilizing the proper enzymes onto the modified electrode surface, different compounds of analytical interest can be determined by means of sensitive, properly designed amperometric biosensors. Analytes such as antioxidant components in extra-virgin olive oils, alcohols in beverages and glucose in food matrices have been tested, using a suitable enzyme: microbial lipase, alcohol dehydrogenase and glucose oxidase, respectively.

The influence of environmental parameters in the biocolonization of the Mithraeum in the roman masonry of casa di Diana (Ostia Antica, Italy).

The microclimatic parameters (Ta, RH, E, and CO2) reflect the indoor quality of the environment. Their relationship, connected with the design of the building, can facilitate the growth of photo/heterotrophic organisms and therefore facilitate the increase of the relative CO2 production. Taking this into account, the impact of biological proliferation in a historical building is discussed for the Mithraeum of "Casa di Diana" in the archaeological site of Ostia Antica, which is subjected to guided tours. In this work, for the first time, we propose a study on biological monitoring to evaluate the contribution of bioactivity to air quality, with the objective to increase the comfort of visitors and to open the site for more than one day per week, suggesting possible tools providing a good compromise between building conservation and human comfort. In the sense, it has been possible to distinguish the contribution of the plants from the one deriving from humans: high values of carbon dioxide have been recorded during the night and its scarce removal during the day (air flow). The window present is not sufficient to eliminate the CO2, involving concentrations of CO2 relatively high in comparison to the proposed limits and guidelines defined by law. The obtained results strongly encouraged the elimination of flora in order to increase the comfort of visitors and to open the house for more than one day per week. Although, this process involves an important economic effort, the present study allows making an objective decision which has an important value in a cultural heritage management. Graphical Abstract CO2 contribute by bioactivity as damage to human health.

Nanostructured enzymatic biosensor based on fullerene and gold nanoparticles: preparation, characterization and analytical applications.

In this work a novel electrochemical biosensing platform based on the coupling of two different nanostructured materials (gold nanoparticles and fullerenols) displaying interesting electrochemical features, has been developed and characterized. Gold nanoparticles (AuNPs) exhibit attractive electrocatalytic behavior stimulating in the last years, several sensing applications; on the other hand, fullerene and its derivatives are a very promising family of electroactive compounds although they have not yet been fully employed in biosensing. The methodology proposed in this work was finalized to the setup of a laccase biosensor based on a multilayer material consisting in AuNPs, fullerenols and Trametes versicolor Laccase (TvL) assembled layer by layer onto a gold (Au) electrode surface. The influence of different modification step procedures on the electroanalytical performance of biosensors has been evaluated. Cyclic voltammetry, chronoamperometry, surface plasmon resonance (SPR) and scanning tunneling microscopy (STM) were used to characterize the modification of surface and to investigate the bioelectrocatalytic biosensor response. This biosensor showed fast amperometric response to gallic acid, which is usually considered a standard for polyphenols analysis of wines, with a linear range 0.03-0.30 mmol L(-1) (r(2)=0.9998), with a LOD of 0.006 mmol L(-1) or expressed as polyphenol index 5.0-50 mg L(-1) and LOD 1.1 mg L(-1). A tentative application of the developed nanostructured enzyme-based biosensor was performed evaluating the detection of polyphenols either in buffer solution or in real wine samples.