A microwave-assisted method for the preparation of a wide color range of 2,3,3-trimethylindolenine-based squaraines and their intermediates is described. This practical approach allows the rapid preparation of both symmetrical and nonsymmetrical squaraine dyes, reducing reaction time from days to minutes with more than 2-fold improvement in product yields when compared to conventional methods.

We report on the design, fabrication, and characterization of optical sensors based on Bloch surface waves propagating at the truncation edge of one-dimensional photonic crystals. The sensors can be simultaneously operated in both a label-free mode, where small refractive index changes at the surface are detected, and a fluorescence mode, where the fluorescence from a novel heptamethyne dye label in the proximity of the surface is collected. The two modes operate in the near-infrared spectral range with the same configuration of the optical reading apparatus. The limit of detection is shown to be smaller than that of equivalent surface plasmon sensors and the fluorescence collection efficiency is such that it can be efficiently analyzed by the same camera sensor used for label-free operation.

Imidazolium based porous cationic polymers were synthesized using an innovative and facile approach, which takes advantage of the Debus-Radziszewski reaction to obtain meso-/microporous polymers following click-chemistry principles. In the obtained set of materials, click based-porous cationic polymers have the same cationic backbone whereas they bear the commonly used anions of imidazolium poly(ionic liquid)s. These materials show hierarchical porosity and good specific surface area. Furthermore, their chemical structure was extensively characterized using ATR-FTIR and SS-NMR spectroscopies, and HR-MS. These polymers show good performance towards carbon dioxide sorption, especially those possessing the acetate anion. This polymer can uptake 2 mmol/g of CO2 at 1 bar and 273 K, a value which is among the highest recorded for imidazolium poly(ionic liquid)s. These polymers were also modified in order to introduce N-heterocyclic carbene along the backbone. Carbon dioxide loading in the carbene containing polymer is in the same range of the non-modified versions, but the nature of the interaction is substantially different. Combined use of in-situ FTIR spectroscopy and micro-calorimetry evidenced a chemisorption phenomenon that brings to the formation of an imidazolium carboxylate zwitterion

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Terpyridine and quaterpyridine-based complexes allow wide light harvesting of the solar spectrum. Terpyridines, with respect to bipyridines, allow for achieving metal-complexes with lower band gaps in the metal-to-ligand transition (MLCT), thus providing a better absorption at lower energy wavelengths resulting in an enhancement of the solar light-harvesting ability. Despite the wider absorption of the first tricarboxylate terpyridyl ligand-based complex, Black Dye (BD), dye-sensitized solar cell (DSC) performances are lower if compared with N719 or other optimized bipyridine-based complexes. To further improve BD performances several modifications have been carried out in recent years affecting each component of the complexes: terpyridines have been replaced by quaterpyridines; other metals were used instead of ruthenium, and thiocyanates have been replaced by different pinchers in order to achieve cyclometalated or heteroleptic complexes. The review provides a summary on design strategies, main synthetic routes, optical and photovoltaic properties of terpyridine and quaterpyridine ligands applied to photovoltaic, and focuses on n-type DSCs.

An efficient and practical synthesis of triaryl and trisindolylmethanes is reported via the bisarylation of aryl aldehydes with activated arenes. The new method features mild solvent-free reaction conditions, in most cases nearly stoichiometric reagent ratios, catalytic amount of the readily available, easily-handled, recoverable and reusable Brønsted acid catalyst o-benzenedisulfonimide.

The design and the synthesis of three unsymmetrical squaraines, DS_34, DS_45, and DS_47, have been achieved for their utilization as sensitizers of screen‐printed NiO cathodes in p‐type dye‐sensitized solar cells (p‐DSCs). DS_34, DS_45, and DS_47 are bidentate dyes, each bearing two carboxylic anchoring groups, which differ solely in the length of alkyl chain attached to the nitrogen atom of the condensed pyrrole ring (ethyl, butyl, and dodecyl for DS_45, DS_34, and DS_47, respectively). The photoelectrochemical properties of the corresponding p‐DSCs are compared and analyzed in terms of the structural differences of DS_34, DS_45, and DS_47. The benchmark dye, p‐SQ2, has also been employed as a p‐DSC sensitizer for the sake of comparison. Current density−voltage (JV) curves and incident photon‐to‐current conversion efficiency (IPCE) spectra revealed the major efficaciousness of the DS_45 as a dye‐sensitizer, as it was the only system that produced a p‐DSC surpassing 0.04 % of overall efficiency (η). This finding was attributed mainly to the larger surface concentration of chemisorbed DS_45 with respect to the other squaraines.

The aim of the present contribution is to prepare a functionalized bioactive glass potentially useful as prosthetic material, but also able to release organic molecules in response to a change of the pH environment. By this approach it is possible to develop devices which can be used for a triggered drug release in response to specific stimuli; this is an attractive research field, in order to avoid either systemic and/or local toxic effects of drugs. In particular, in the present paper we report data related to the development of a new formulation of bioactive glasses, their functionalization with organic molecules to obtain a pH-sensitive bond, their physicochemical characterization and in vitro bioactivity in simulated biological fluids (SBF), and organic molecule delivery tests at different pH. The glass functionalization, by means of a covalent reaction, allows us to produce a model of pH-responsive bioactive biomaterial: when it is exposed to specific pH changes, it can favor the release of the organic molecules directly at the target site. Cysteamine and 5-aminofluorescein are used as model molecules to simulate a drug. The materials, before and after the different functionalization steps and in vitro release tests at different pH, have been characterized by means of different experimental techniques such as X-ray powder diffraction (XRPD), Raman, FTIR and fluorescence spectroscopies, N2 adsorption, thermogravimetric (TGA) and elemental analysis.