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Herein we report the effect of different nucleobase pair compositions on the association-induced fluorescence enhancement property of Thioflavin T (ThT), upon binding with 20 base pair long double-stranded DNA (dsDNA). Analysis of binding and decay constants along with the association (K ass ) and dissociation (K diss ) rate constants obtained from the fluctuation in the fluorescence intensity of ThT after binding with different DNA revealed selective affinity of ThT toward AT-rich dsDNA. Molecular docking also substantiates the experimental results. We also observed that addition of orange-emitting ethidium bromide (EtBr) to cyan-emitting ThT−DNA complexes leads to bright white light emission (WLE) through Forster resonance energy transfer. Additionally, the emission of white light is far greater in the case of intra-DNA strands. Besides endorsing the binding insights of ThT to AT-rich dsDNA, the present investigations open a new perspective for realizing promising WLE from two biomarkers without labeling the DNA.

At the ALADIN-LAND setup at GSI the unbound nucleus 13 Be has been produced in one-neutron knockout reactions from a 304 MeV/nucleon relativistic beam of 14 Be ions impinging on a liquid hydrogen target. An analysis of the data including all available information about 13 Be, and in particular recent data from a similar experiment performed at RIKEN, has been performed. A consistent description is reached. It is found that the excitation spectrum is dominated by s-waves at low energy, which solves problems from previous seemingly contradictory interpretations. A possible interference between two s-states in 13 Be is also discussed. The results indicate that the ground-state wave function of 14 Be is dominated by valence neutrons in the s-shell contributing with 60-75% of the total neutron knockout cross section.

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