A Neutral Flavin-Triphenylamine Probe for Mitochondrial Bioimaging under Different Microenvironments.

A bioinspired design built around a neutral flavin-triphenylamine core has been investigated for selective mitochondrial bioimaging capabilities in different microenvironments. Significant advantages with respect to long-term tracking, faster internalization, penetrability within the spheroid structures, and strong emission signal under induced hypoxia conditions have been observed, which could offer an alternative to the existing mitotrackers for hypoxia-related biological events.

Investigating the spectral and electrochemical properties of novel flavin-pyrene dyads separated via variable spacer.

The present manuscript describes the synthesis and the photophysical properties of a pair of novel flavin-pyrene dyads where the donor and the acceptor entities are separated via variable spacer. The dyads were well characterized using standard techniques and investigated for their photophysical and electrochemical nature. The observed absorption spectra of the dyads mainly display peaks corresponding to the individual pyrene and flavin units, with some contribution from the flavin entity in the pyrene region. While, strong emission quenching was observed for both the dyads if compared to its individual constituents. However, a careful analysis of the emission spectra and the solvent dependent studies reveals subtle difference between the two dyads. While no significant difference could be observed when excited in the flavin region; excitation at the pyrene region displays a weak and broad emission band in case of closely connected dyad. Further, the electrochemical properties were investigated by cyclic voltammetry and the reduction ability was observed to follow the trend as FlPy2 < FlPy1 < Fl.

Luminescence and morphological behaviour of the aromatic dipeptide pair having singular structural variability.

In the present manuscript, the luminescence and the self-assembly behaviour of two aromatic dipeptides with a singular structure variable are investigated. The terminally protected dipeptides tryptophan-tyrosine (WYp ) and tryptophan-phenylalanine (WFp ) were synthesized using a standard solution phase procedure. Significant solvatochromic effect was observed for both the dipeptidyl entities; whilst the influence was more pronounced for the WYp entity when compared with WFp . Interesting morphological variation was observed for WFp and WYp , in which discrete and interconnected nanospheres were observed for the respective dipeptides. The results obtained signify the influence of the singular structural variation on modulating the overall functional behaviour of the short peptides motifs.