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The in situ synthesis and patterning of CdS nanocrystals (NCs) is obtained by laser processing of a transparent polymer matrix doped with a cadmium thiolate methylimidazole (MI) modified complex, [Cd(SBz)2]2·MI. The precursor molecule structure ensures a uniform distribution inside the polymer and gives rise to a regular and homogeneous network of CdS NCs in the quantum size regime with a finely tunable bandgap by varying the laser fluence in the range 25–75 mJ cm–2and shot number from 10 to 100. The simultaneous in situ synthesis of CdS NCs and patterning has been performed in confined regions with a 10 μm resolution by scanning the focused laser beam in the polymer/precursor composite. The emission signal of the irradiated regions presents contributions from both the band gap and the defect emission band, around 3.4 and 2.2 eV, respectively, the relative intensity of them depending on the laser fluence and number of shots. Complex geometries of μ-patterned CdS NCs inside the polymer matrix are achievable, thus enlarging the perspectives in the development of nanodevices and organic light emitting diode (OLED) systems.

We investigated the structural changes occurring in proteins patterned via microcontact printing. This was done by molecular sizing using atomic force microscopy to observe the structure of printed individual metalloprotein molecules in the unlabeled and untreated states. We observed that the size of the printed proteins were more than 2-fold smaller than the native shape, which indicates that some deformations take place upon the contact-assisted adsorption on silanized silicon dioxide. This can be attributed to simultaneously occurring effects, and particularly to the sandwiching between surfaces of very different hydrophilic/hydrophobic properties during contact lithography.

The waveguiding properties and amplified spontaneous emission (ASE) of a blend of light-emitting gain-conjugated polymers were investigated. ASE-induced line narrowing occurs for excitation fluences larger than 100 μJcm^−2, with a maximum optical-gain coefficient of 8 cm^−1. Energy transfer between the host and guest polymers, significantly reducing the self-absorption, leads to a loss coefficient of the waveguide as low as 0.3 cm^−1, which is believed to be the lowest value reported for active organic gain slabs and a highly polarized emission, with a polarization contrast up to 0.65. These results indicate that gain-conjugated polymer blends are state-of-the-art organic materials for lasing devices.

The growing demand for new solutions to pursue the trend of micro- and nanoelectronics predicted by Moore's law is stimulating the development of new high-resolution, low-cost lithographies. Here we demonstrate that several bottom-up approaches can be used to increase the throughput of soft lithography by exploiting the enhanced hydrophilicity, the low viscosity, and the fragility of the employed materials. In particular, the customized functionalization of the involved surfaces to improve the wettability to polymer fluids and the dramatic decrease of the viscosity of polymer compounds as the temperature is increased, together with the good thermal stability of the functionalized surfaces, allow a faster filling of elastomeric channels, up to almost an order of magnitude with respect to conventional microfluidics.