Enhancing the Sensitivity of Biotinylated Surfaces by Tailoring the Design of the Mixed Self-Assembled Monolayer Synthesis

Thiolated self-assembled monolayers (SAMs) are typically used to anchor on a gold surface biomolecules serving as recognition elements for biosensor applications. Here, the design and synthesis of N-(2-hydroxyethyl)-3-mercaptopropanamide (NMPA) in biotinylated mixed SAMs is proposed as an alternative strategy with respect to on-site multistep functionalization of SAMs prepared from solutions of commercially available thiols. In this study, the mixed SAM deposited from a 10:1 solution of 3-mercaptopropionic acid (3MPA) and 11-mercaptoundecanoic acid (11MUA) is compared to that resulting from a 10:1 solution of NMPA:11MUA. To this end, surface plasmon resonance (SPR) and attenuated total reflectance infrared (ATR-IR) experiments have been carried out on both mixed SAMs after biotinylation. The study demonstrated how the fine tuning of the SAM features impacts directly on both the biofunctionalization steps, i.e., the biotin anchoring, and the biorecognition properties evaluated upon exposure to streptavidin analyte. Higher affinity for the target analyte with reduced nonspecific binding and lower detection limit has been demonstrated when NMPA is chosen as the more abundant starting thiol. Molecular dynamics simulations complemented the experimental findings providing a molecular rationale behind the performance of the biotinylated mixed SAMs. The present study confirms the importance of the functionalization design for the development of a highly performing biosensor

Considerations on the role of POs: analysis of a case study

The Italian agricultural sector is facing new challenges and, for this reason, needs to introduce new models of governance that contribute to development of the agro-food chain from the farm. A new opportunity derives by the new 2014-2020 European programs, which allocated funds, aimed at promoting innovation/internationalization in the development of enterprise. In particular, the new regime of the Common Agricultural Policy (CAP) supports the operational programs to be implemented by Producer Organizations (POs) and Producers Organizations Association (POAs) properly recognized by funding contributions from the operational funds of programs according to the EC Regulation. 1308/2013 and the Ministerial Decree n. 9083 of 28 August 2014. In this context, it can be significant to establish an POA composed of groups of POs whose members are the POs partners involved in a transnational cooperation project. With this form of internalization, it is possible to create a model of governance between farms, and not of different States that pursue the same objectives in terms of economic and rural development, capable of bringing economic, environmental and social benefits

An input flow analysis for improved environmental sustainability and management of cherry orchards: A case study in the Apulia region

Italy is the fourth top world cherries producer after Turkey, United States of America, Iran (Islam Republic of). The Apulia region is the largest sweet cherries (Prunus avium L.) producer at the national level and in particular one of the most produced cultivar is “Ferrovia”. This work is based upon a life-cycle approach, and is aimed at collecting and analysing the material and energy input-flows associated with a cherry orchard in the Apulia region. The study is intended both to serve as the starting base for performing the next phases of life-cycle inventory and environmental impact assessment, and to contribute in enhancing the current databases and scientific literature in this field. Furthermore, the study allowed the authors to highlight that the major inputs were due both to irrigation as large volumes of water used and diesel fuel consumption in particular to fertiliser and pesticide transportation and administration. The study can be considered as bases for further evaluation and reduction of the related environmental impacts

Self-powered logically operated fluorescent detection of hepatitis B virus (HBV)

In this study, a novel sensing strategy based on double sensing/actuating pathway is demonstrated, being capable to trigger the DNA-based AND gate for the sensitive and selective detection of hepatitis B virus DNA (HBV-DNA). Such an approach encompasses an enzymatic machinery logically operated using the variation of physiologically relevant biomarkers for liver dysfunctions. Alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) are used as inputs of an AND gate generating an output signal, namely lactate. In particular, lactate is oxidized back to pyruvate at the anodic electrode by lactate oxidase connected in mediated electron transfer through ferrocene moieties (creating an amplifying recycling mechanism). The anodic electrode is further connected with a Myrothecium verrucaria bilirubin oxidase (MvBOx) based biocathode modified with SiO2 nanoparticles (SiO2NPs) functionalized with phenyl boronic acid and trigonelline, triggering the release of quenching DNA (qDNA) upon local pH change at the electrode surface (notably, modified SiONPs gets negatively recharged upon local pH gradient releasing negatively charged DNA). Next, the released qDNA labeled with BHQ2 and detecting DNA (dDNA, labeled with FAM) are detecting HBV-DNA. The proposed biosensor can discriminate between the absence and presence of HBV-DNA setting the threshold at 0.05 fM in model buffer solutions and 1 fM in human serum. This enzymatic/DNA logic network can be of particular interest for future biomedical applications (e.g., early detection of liver cancer disease etc.). In the future development this technology could be easily integrated with a smartphone camera, allowing more user-friendly applications

Carbon footprint of processed sweet cherries (Prunus avium L.): From nursery to market

The implementation of scientific studies can help to improve sustainable solutions in the agri-food sector according to current European policy. The present paper aims to evaluate the carbon footprint, according to ISO/TS 14067:2013, of 0.5 kg of sweet cherries packaged in clamshell made in polyethylene terephthalate (PET). The research assesses the supply chain, from agricultural (from nursery to dismantling) to the processing phase in firms located in the Apulia region. Results show a global warming potential over a fixed period corresponding to 100 years equal to 0.584 kg CO2eq, primarily deriving from agricultural management (0.442 kg CO2eq) and secondly from fruit processing (0.068 kg CO2eq). In the orchard phase, the main impacts derived from electricity consumed to pump groundwater used for irrigation and fertigation activities (15.84% of the total), transportation of manure (6.42% of the total), ploughing activity (4.83% of the total) and production of nitrogen fertilisers (4.28% of the total). Cherries processing in the collecting centre showed impacts from electricity consumption (5.57% of the total) and from waste deriving from damaged or non-conforming cherries (4.74% of the total). The PET clamshell production phase had an impact deriving principally from the use of PET granulate (0.0743 kg CO2eq). The study highlighted that manure administration and pruning activities contribute to decreasing greenhouse gas (GHG) emissions. Moreover, the sensitivity analysis showed that substitution of electricity-mix deriving from the Italian national grid with a photovoltaic plant lowered GHG emissions by 19%. The present study could contribute in providing suggestions to stakeholders and scholars in reducing GHG emissions and promoting more environmentally sustainable sweet cherry production practices