Going Platinum to the Tune of a Remarkable Guanine Quadruplex Binder: Solution- and Solid-State Investigations.

Guanine quadruplex recognition has gained increasing attention, inspired by the growing awareness of the key roles played by these non-canonical nucleic acid architectures in cellular regulatory processes. We report here the solution and solid-state studies of a novel planar platinum(II) complex that is easily assembled from a simple ligand, and exhibits notable binding affinity for guanine quadruplex structures, while maintaining good selectivity for guanine quadruplex over duplex structures. A crystal structure of this ligand complexed with a telomeric quadruplex confirms double end-capping, with dimerization at the 5' interface.

Characterization of acetylated starch nanoparticles for potential use as an emulsion stabilizer.

To overcome the low production efficiency of Pickering emulsion stabilizers prepared from starch, alcohol precipitation and surface modification were applied in this study. Spherical starch nanoparticles (StNPs) (247.90 ± 1.96 nm) were prepared through nanoprecipitation. The StNPs were surface-esterified to produce starch nanoparticle acetate (StNPAc), and the physicochemical changes of the products were investigated. The contact angle (>89.56° ± 0.56°) of StNPAc (degree of substitution, 0.53) was maintained for over 30 min. The results showed that the hydrophobicity of the StNPs was improved by shielding the surface hydroxyl groups via acetylation. StNPAc was also used to produce emulsions for further evaluation of their feasibility as Pickering emulsifiers. Oil-in-water (3:7, v/v) emulsions containing 1.5 wt% StNPAc were stabilized for over 35 days without creaming. Thus, StNPAc exhibited better emulsifying capacity and storage stability than StNPs. Therefore, hydrophobic starch nanoparticles obtained by acetylation are promising stabilizers for surfactant-free Pickering emulsions.