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We present and discuss results on the thermal behaviour of 1,2,3,4,5,6,7,8-octahydroacridine (OHA), together with six 9-substituted congeners, i.e. R = -Br, -OCH, -NH, -NO, -OH, and furyl (-CHO), and their corresponding N(10)- oxides, under nitrogen atmosphere and with alumina as reference, at a heating rate of 5 °C min from room temperature to 300 °C. Chromatography has been carried out on aluminium sheets, with aluminium oxide 60 F254 neutral (Merck). Melting effects are observed for almost all compounds in their corresponding curves, precisely determined by using a Boetius apparatus. Homolysis of the carbon-substituent bond occurs in most cases, a phenomenon which is consistent with the values of the bond dissociation energy. For all compounds, except for hydroxyl congeners, thermal decomposition started with an endothermic peak. Octahydroacridines readily decompose into volatile products, an effect which correlates with their low melting points, while little amounts of residue remain in place of the aromatic amines compared to the N(10)-oxides. The presence of N-O bonds greatly influences the thermal stability of the compound, in the sense of increasing it compared with the parent amine. Quantitative studies of the decomposition products reveal that the melting points, the 9-position substituent, and N-O bond all play an important role upon the thermal behaviour. Mechanistic/kinetic pathways are also proposed as such results are important in further designing laser processing protocols, i.e. matrix-assisted pulsed laser evaporation (MAPLE) or laser-induced forward transfer (LIFT), for thin film deposition and/or device printing. [ABSTRACT FROM AUTHOR]

Laser-induced forward transfer (LIFT) has been investigated for the transfer of a polymeric material. This study focuses on the comparison of the printing process using conventional LIFT printing with a simple square mask and an optimized LIFT technique using a double mask setup, i.e. smart beam shaping (SBS). The purpose is to optimize the energy repartition on the donor layer using a beam profile with over-intensities at the edges and low intensities in the center. This allows the incoming irradiation fluence on the donor layer to be kept as low as possible in the central area, thus preventing the organic pixels being damaged by laser irradiation. The influence of the film's thickness on the SBS efficiency is discussed. [ABSTRACT FROM AUTHOR]

In this work, antitumor compounds, lactoferrin [recombinant iron-free (Apo-rLf)], cisplatin (Cis) or their combination were embedded within a biodegradable polycaprolactone (PCL) polymer thin film, by a modified approach of a laser-based technique, matrix-assisted pulsed laser evaporation (MAPLE). The structural and morphological properties of the deposited hybrid films were analyzed by Fourier-transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM). The in vitro effect on the cells' morphology and proliferation of murine melanoma B16-F10 cells was investigated and correlated with the films' surface chemistry and topography. Biological assays revealed decreased viability and proliferation, lower adherence, and morphological modifications in the case of melanoma cells cultured on both Apo-rLf and Cis thin films. The antitumor effect was enhanced by deposition of Apo-rLf with Cis within the same film. The unique capability of the new approach, based on MAPLE, to embed antitumor active factors within a biodegradable matrix for obtaining novel biodegradable hybrid platform with increased antitumor efficiency has been demonstrated. [ABSTRACT FROM AUTHOR]

A new synthesized 4CN type azomonoether, exhibiting dying properties, crystalline nature and generating interest as a material for non-linear optical applications was investigated. Modern devices incorporating liquid crystals tend to use thin films of such materials because of their special characteristics. Thermal stability studies are indispensable before attempting any deposition experiment. We have investigated the thermal behaviour of 4-[(4-chlorobenzyl)oxy]-4′-cyano-azobenzene (TG, DTG, DTA and DSC) in inert flow atmosphere, under non-isothermal conditions. The phase transitions were studied by repeated heating-cooling regimes, with intercalated isothermal steps. The thin films were deposited on silicon and quartz substrates by matrix assisted pulsed laser evaporation (MAPLE) using a Nd:YAG laser working at 266 nm. FTIR spectroscopy of the obtained thin films confirmed the preservation of the compound’s structure. [ABSTRACT FROM AUTHOR]