0000000000116818
AUTHOR
Julie P. Vanegas
A tailor-made nucleoside-based colourimetric probe of formic acid
A ratiometric, specific probe of formic acid has been developed. It is based on intermolecular nucleobase-pairing of inosine-capped plasmonic nanoparticles to form nucleoside channels, which are destabilised by the analyte.
Adenosine monophosphate-capped gold(i) nanoclusters: synthesis and lanthanide ion-induced enhancement of their luminescence
Reduction of Au3+ in the presence of just adenosine 5′-monophosphate (AMP) and a zwitterionic organic chemical buffering agent, specifically 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES), combined with light exposure, gives rise to luminescent, water-soluble Au+ nanoclusters (Au+ NCs). The photoluminescence of these NCs is considerably enhanced by adding Y3+ or the chemically similar Yb3+ lanthanide that leads to Au+/Y3+ and Au+/Yb3+ NCs, respectively. These NCs are characterised by absorption (steady-state), photoluminescence (steady-state and time-resolved), and X-ray photoelectron spectroscopy.
Water-Soluble Naked Gold Nanoclusters Are Not Luminescent.
We report here the synthesis of water-dispersible naked gold nanoclusters (AuNCnaked) by a simple reduction of HAuCl4 with NaOH at room temperature and show that they are non-luminescent. They were then easily passivated with different thiols and adenosine monophosphate to lead to luminescent NCs. This is an important finding as the photoluminescence of the passivated NCs can now be clearly attributed to the ligand-AuNC surface interaction. These results are also highly relevant from the point of view of the preparation of luminescent NCs from the same NC batch. This strategy can be valuable for the preparation of a broad range of nano(bio)composites.
Unzipping Nucleoside Channels by Means of Alcohol Disassembly
Gold nanoparticles capped with simple adenosine derivatives can form colloidal aggregates in nonpolar solvents. Theoretical calculations indicate the formation of organic channels by the supramolecular assembly of the nanoparticles by means of hydrogen bonds between the adenine moieties. The aggregates were only negligibly sensitive to nPrOH, iPrOH, and tBuOH, whereas some showed a similar response to MeOH and EtOH, and others showed high selectivity toward MeOH. DNA nucleoside derivatives (1-(2-deoxy-β-D-ribofuranosyl)-5-methyluracil and 2′,3′-O-isopropylideneadenosine) as well as thymine and other aromatic compounds such as pyrene derivatives (pyrene, 1-chloropyrene, 1-hydroxypyrene, (1-p…