The effect of complementary base pairing on the oxidation potential of a guanosine derivative has been determined by cyclic and differential pulse voltammetry in CHCl3. The formation of the Watson-Crick H-bonded complex lowers the oxidation potential of the free molecule by 0.34 V, which compares well with the value obtained by DFT/B3LYP/6-311++g** computations.

Pollution by metal and metalloid ions is one of the most widespread environmental concerns. They are non-biodegradable, and, generally, present high water solubility facilitating their environmental mobilisation interacting with abiotic and biotic components such as adsorption onto natural colloids or even accumulation by living organisms, thus, threatening human health and ecosystems. Therefore, there is a high demand for effective removal treatments of heavy metals, making the application of adsorption materials such as polymer-functionalized nanocomposites (PFNCs), increasingly attractive. PFNCs retain the inherent remarkable surface properties of nanoparticles, while the polymeric support materials provide high stability and processability. These nanoparticle-matrix materials are of great interest for metals and metalloids removal thanks to the functional groups of the polymeric matrixes that provide specific bindings to target pollutants. This review discusses PFNCs synthesis, characterization and performance in adsorption processes as well as the potential environmental risks and perspectives.

The self-assembling of fluorescent guest molecules, with the δ nanoporous host crystalline phase of syndiotactic polystyrene (s-PS) films, reduces chromophore diffusivity. Moreover, the chromophore fluorescence can be largely perturbed by formation of suitable polymer co-crystals. In particular, by excitation at the absorbance maximum (≈265 nm), s-PS/1,3,5-trimethylbenzene clathrate co-crystals present a broad fluorescence band nearly centered at 300 nm, while the corresponding intercalate co-crystals present a red-shifted fluorescence band with maxima at 330, 340, and 355 nm. This red shifted fluorescence is possibly due to absorption of the primary fluorescence by ground state complexes, formed in the intercalate co-crystal. The enhanced and red-shifted fluorescence could be relevant for optical and optoelectronic applications.

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