This study reports on the potential of comprehensive two-dimensional gas chromatography combined with time-of-flight mass spectrometry (GC×GC−ToF MS) for the exhaustive untargeted characterization of the volatile and semi-volatile analytes migrating from four commercial polypropylene food containers into four simulants (water, 3% acetic acid, 10% ethanol, and isooctane) according to European Regulation 10/2011. Collected extracts were concentrated and directly subjected to GC×GC−ToF MS analysis without any further treatment to preserve migrants integrity. As expected, the nature and total number of compounds detected in the migrates depended on both the brand (i.e., manufacture and/or sterilization procedure) and the simulant applied. In total, 107 analytes, including some less volatile compounds, were either positively or tentatively identified in the investigated simulants, a number of these compounds being reported for the first time as migrants from this type of material. A database containing chromatographic, mass spectral and partition information concerning these compounds, plus 23 remaining unidentified, is provided.

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Here, we present the design of smart nanodevices capable of reading molecular information from the environment and acting accordingly by processing Boolean logic tasks. As proof of concept, we prepared Au-mesoporous silica (MS) nanoparticles functionalized with the enzyme glucose dehydrogenase (GDH) on the Au surface and with supramolecular nanovalves as caps on the MS surface, which is loaded with a cargo (dye or drug). The nanodevice acts as an AND logic gate and reads information from the solution (presence of glucose and nicotinamide adenine dinucleotide (NAD)), which results in cargo release. We show the possibility of coimmobilizing GDH and the enzyme urease on nanoparticles to mimic an INHIBIT logic gate, in which the AND gate is switched off by the presence of urea. We also show that such nanodevices can deliver cytotoxic drugs in cancer cells by recognizing intracellular NAD and the presence of glucose.

A novel water-soluble graphene derivative was prepared from graphene oxide via a two-step modification approach. Graphene oxide was first functionalised with reactive epoxy groups by covalent modification with (3-glycidyloxypropyl)trimethoxysilane and further cross-linked with glycol chitosan. This graphene derivative was characterized using different microscopy and physicochemical methods and employed as a coating material for a glassy carbon electrode. The nanostructured surface was used as a support for the covalent immobilization of the enzyme laccase through cross-linking with glutaraldehyde. The enzyme electrode was tested for the amperometric detection of different phenolic compounds, which displayed excellent analytical behaviour toward catechol with a linear range of response from 200 nM to 15 μM, sensitivity of 93 mA M(-1) cm(-2), and low detection limit of 76 nM. The enzyme biosensor showed high stability when stored at 4 °C under dry conditions and was successfully employed to quantify the total phenolic compounds in commercial herbal tea samples.

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