Enacting Two-Electron Transfer from a Double-Triplet State of Intramolecular Singlet Fission.

A simulation-led strategy enacts two-electron transfer between an intramolecular singlet fission chromophore (tetracyanomethylene quinoidal bithiopehene with β,β'-solubilizing groups) and multielectron acceptor (anthraquinone). The thermodynamic plausibility of multielectron transfer from a double-triplet state and the absorption spectra of electron transfer (ET) products were predicted using quantum chemical simulations. These predictions are consistent with experimental observations of reduced lifetimes in time-resolved fluorescence spectroscopy, changes in transmission profile, and appearance of new absorption bands in transient absorption spectroscopy, all of which support multi-ET in the QOT2/AQ mixture.

Efficient Singlet Oxygen Generation in Metal Nanoclusters for Two-Photon Photodynamic Therapy Applications.

The generation of singlet oxygen (O) has been established as the principal mechanism of photodynamic therapy (PDT). Various dyes, metal nanoparticles, and clusters have been shown to sensitize O. However, metal nanoclusters are even more promising candidates as photosensitizers for this purpose.

Linear and Nonlinear Optical Properties of Monolayer-Protected Gold Nanocluster Films.

Gold nanoclusters have been extensively studied in solution for their unique optical properties. However, many applications of nanoclusters involve the use of the material in the solid state such as films. Au25(SR)18 in polymeric hosts was used as the model for studying the optical properties of nanocluster films.

Synthesis of Ladder-Type Thienoacenes and Their Electronic and Optical Properties.

A series of ladder-type thienoacenes based on benzo[1,2-b:4,5-b']dithiophene (BDT) have been synthesized and characterized. They were shown to be p-type semiconductors with wide band gaps and able to support multiple stable cationic states. As the conjugation lengthens, these oligomers become more emissive, showing high quantum yields.

The Impact of Surface Ligands and Synthesis Method on the Toxicity of Glutathione-Coated Gold Nanoparticles.

Gold nanoparticles (AuNPs) are increasingly used in biomedical applications, hence understanding the processes that affect their biocompatibility and stability are of significant interest. In this study, we assessed the stability of peptide-capped AuNPs and used the embryonic zebrafish () as a vertebrate system to investigate the impact of synthesis method and purity on their biocompatibility. Using glutathione (GSH) as a stabilizer, Au-GSH nanoparticles with identical core sizes were terminally modified with Tryptophan (Trp), Histidine (His) or Methionine (Met) amino acids and purified by either dialysis or ultracentrifugation.

A facile route to tailoring peptide-stabilized gold nanoparticles using glutathione as a synthon.

The preparation of gold nanoparticles (AuNPs) of high purity and stability remains a major challenge for biological applications. This paper reports a simple synthetic strategy to prepare water-soluble peptide-stabilized AuNPs. Reduced glutathione, a natural tripeptide, was used as a synthon for the growth of two peptide chains directly on the AuNP surface.