Chemical treatments involving supercritical fluids are of interest in order to add functionality into the core of polymer parts. Moisture absorption in polyamides damages their mechanical properties in operation. Stability of injected commercial PA 6–6 glass fiber composites towards steam ageing was improved with various hydrophobic molecules grafted to the polymer chain network under supercritical fluids. The interest of both CO2 and butane as supercritical fluids was investigated regarding their impact on the mechanical properties as well as on the chemical penetration in the samples. The development of the mechanical properties of the treated parts was followed during the steam ageing test. Further supercritical treatments combining two types of molecules with different hydrophobic tails could reduce the water uptake by 46%. The surface hydrophobicity of the treated samples remained almost unchanged after the steam ageing test, with a water contact angle remaining higher than 100°.

A method based on FTIR spectroscopy was proposed for monitoring the biological effects induced on human renal cells with SiO2 nanoparticles (NPs).

Glucose oxidase is immobilized on a ZnO-Fc nanoparticle modified electrode. The new architecture of ZnO supported electron mediators to shuttle electrons from the redox centre of the enzyme to the surface of the working electrode can bring about successful glucose oxidation.

This paper highlights the way in which eukaryotic cell and bacteria based biochips are relevant for nanotoxicological risk assessment.

The paper reviews a selection of synthetic pathways that provide access to 3,6-disubstituted phthalonitriles, precursors for the synthesis of 1,4,8,11,15,18,22,25-octasubstituted phthalocyanine derivatives. Early routes using Diels–Alder reactions for the synthesis of 3,6-dialkyl, 3,6-dialkoxymethyl, 3,6-dialkenyl and 3,6-diphenylphthalonitriles are appraised. However, the emphasis of the review focuses on the scope and applications of 2,3-dicyanohydroquinone as a starting material for obtaining 3,6-disubstituted phthalonitriles. The earliest example of the use of 2,3-dicyanohydroquinone concerned its O -alkylation to afford 3,6-dialkoxyphthalonitriles. These are immediate precursors to near-infrared absorbing phthalocyanine derivatives. Triflation of 2,3-dicyanohydroquinone extends the scope of the compound for phthalocyanine synthesis; the bis-triflate derivative is susceptible to S N Ar reactions and readily reacts with thiols to provide 3,6-bis(alkylsulfanyl) and 3,6-bis(arylsulfanyl)phthalonitriles. 3,6-Bis(phenylselenyl)phthalonitrile has also been obtained recently from the same precursor. Phthalocyanine derivatives obtained from them typically show a strongly bathochromically shifted Q-band absorption that is particularly sensitive to the central metal ion. The bis-triflate of 2,3-dicyanohydroquinone is also an ideal precursor for participation in cross-coupling reactions. Examples from the University of East Anglia group and elsewhere are presented which show the application of the nickel-catalyzed Negishi coupling reaction using alkylzinc halide derivatives. Yields of 3,6-dialkylphthalonitriles and 3,6-bis(substituted alkyl)phthalonitriles range from ca. 40 to 70%. Direct comparison for one example shows that the yield from the Negishi coupling method is higher than that using the Suzuki coupling protocol. Examples of the preparation of 3,6-diarylphthalonitriles from 2,3-dicyanohydroquinone bis-triflate using the Suzuki coupling reaction are reported with yields of the order of 65–70%. The review also includes a further application of 2,3-dicyanohydroquinone as a precursor to both monobromo and dibromo derivatives of 3,6-dibutoxyphthalonitrile. These compounds provide opportunities for cross-coupling at the brominated sites to provide more complex derivatives with the potential to serve as precursors of highly substituted phthalocyanine derivatives.

Numerous luminophores may be encapsulated into silica nanoparticles (< 100 nm) using the reverse microemulsion process. Nevertheless, the behaviour and effect of such luminescent molecules appear to have been much less studied and may possibly prevent the encapsulation process from occurring. Such nanospheres represent attractive nanoplatforms for the development of biotargeted biocompatible luminescent tracers. Physical and chemical properties of the encapsulated molecules may be affected by the nanomatrix. This study examines the synthesis of different types of dispersed silica nanoparticles, the ability of the selected luminophores towards incorporation into the silica matrix of those nanoobjects as well as the photophysical properties of the produced dye-doped silica nanoparticles. The nanoparticles present mean diameters between 40 and 60 nm as shown by TEM analysis. Mainly, the photophysical characteristics of the dyes are retained upon their encapsulation into the silica matrix, leading to fluorescent silica nanoparticles. This feature article surveys recent research progress on the fabrication strategies of these dye-doped silica nanoparticles.

Fluorescent silica nanoparticles are widely used for various applications from mechanical reinforcement to biology. In many cases, their surface has to be tailored. Herein fluorescent silica nanoparticles are synthesized by a reverse micro-emulsion process and functionalized by silane coupling agents owning amino and thiol groups. The functionalization is then characterized by macroscopic well-known methods (zeta potential, hydrophilic to hydrophobic ratio, etc.) and an original method based onto TEM observations of the contrast between the silica core and the metallic ions chelated by the functional groups grafted onto the surface is also introduced. This method reveals that the functionalization is effective and that it occurs by “nano domains.” It is therefore possible to characterize the functionalization by in situ observations. Finally, the characterized nanoparticles are incorporated into a PMMA thin film. The fluorescence of the nanoparticles allows the monitoring of the level of dispersion of the nanoparticles within the polymer and confirms all the other characterizations.

Two different condensations of appropriate dipyrromethanes and aldehydes resulted in two structural isomers of metal-free, meso-substituted diferrocenyldipentafluorophenyl porphyrins, one with the ferrocenyl groups in the 5,15 positions, 6, and the other with the ferrocenyl groups in the 5,10 positions, 7. UV/vis spectroscopic and cyclic voltammetric (CV) techniques could not unambiguously distinguish between the isomers, but H-1 NMR clearly distinguished between them. Use of the CH2Cl2/0.1M [N(Bu-n)(4)][B(C6F5)(4)] solvent/supporting electrolyte system allowed good resolution between the two ferrocenyl CV waves with Delta E degrees' = 111 and 115 mV for 6 and 7, 102 mV for the Zn derivative of 6, namely 8, and 109 mV for 6's Ni derivative, 9. Delta E degrees' values for the Zn (10) and Ni (11) derivatives of 7 were 103 and 95 mV, respectively. The formal reduction potentials, E degrees', at which the two observed ring-based electrochemical reductions and one oxidation process were detected, varied in a manner that depended on the cationic electronegativities, chi(Zn2+) or chi(Ni2+), of the coordinated central cations. Differences in E degrees' of 6-11 with respect to that of meso tetraphenyl porphyrin, 2Htpp, were found to be related to the group electronegativities, chi(C6H5), chi(C6F5), chi(Fc), and chi(Fc+), of each meso substituent.

Selective condensation of 5-ferrocenyldipyrromethane, 1, and dipyrromethane, 2, with benzaldehyde, 3, led to 5-ferrocenyl-10,20-diphenylporphyrin, 5. During the condensation, an unusually large amount of scrambling was observed which led to the isolation of two further ferrocenylated porphyrin analogues 6 and 7. The structure of 6 was confirmed by a single-crystal X-ray study. A mechanism is proposed for this atypical scrambling which is likely to involve acid-catalysed reversion of the dipyrromethane synthesis. (1)H NMR further elucidated the structures of each complex and showed the existence of atropisomerism. An electrochemical study (cyclic voltammetry, Osteryoung square wave and linear sweep voltammetry) showed that there exists a linear relationship between the sum of the group electronegativities of meso substituents of the obtained porphyrins and the formal reduction potentials of the two observed ring-centred reduction processes, the meso substituent ferrocenyl-based oxidation process and the first ring-centred oxidation wave. These four relationships could be mathematically quantified. Due to the strong electron-withdrawing properties of the oxidised ferrocenium group, the second ring centred oxidation wave fell outside the potential window of dichloromethane as solvent.