A unique pH-driven Förster resonance energy transfer (FRET) based biosensor emission by a pyrazoline-doxorubicin pair has been deciphered with a bioimaging application in a live HepG2 cell whereas conformational switching of both molecules at elevated pH reveals a fascinating twist (FRET-OFF) via strong fluorescent exciplex formation.

We give a Parrondo’s paradox of free energy in the classical flashing ratchet model, which is a different viewpoint from the existing examples. Further, we show that the Parrondo’s paradox of free energy gives a different viewpoint of molecular motor, with which we may analysis its efficiency. Our example shows that the molecular motors can gain up to 20% in the free energy during the process. ...

A sensitive and specific fluorescence resonance energy transfer (FRET) biosensor was developed by Mizutani and colleagues and applied to detect the activity of BCR-ABL kinase in live cells. This biosensor allowed the detection of cancerous and drug-resistant cells, and the evaluation of kinase inhibitor efficacy. Future biosensor development and imaging can increasingly contribute to cancer dia...

To date, single-molecule RNA science has been developed almost exclusively around the effect of metal ions as folding promoters and stabilizers of the RNA structure. Here, we introduce a novel strategy that combines single-molecule Förster resonance energy transfer (FRET) and chemical denaturation to observe and manipulate RNA dynamics. We demonstrate that the competing interplay between metal ...

Live-cell microscopy is now routinely used to monitor the activities of the genetically encoded biosensor proteins that are designed to directly measure specific cell signaling events inside cells, tissues, or organisms. Most fluorescent biosensor proteins rely on Förster resonance energy transfer (FRET) to report conformational changes in the protein that occur in response to signaling events,...

Fluorescence lifetime imaging (FLIM) when paired with Förster resonance energy transfer (FLIM-FRET) enables the monitoring of nanoscale interactions in living biological samples. FLIM-FRET model-based estimation methods allow the quantitative retrieval of parameters such as the quenched (interacting) and unquenched (non-interacting) fractional populations of the donor fluorophore and/or the dis...

Förster resonance energy transfer (FRET) is a phenomenon used for bioimaging ranging from single molecules to in vivo scale. A large variety of organic dyes and fluorescent proteins are available for FRET probes. In this review, we introduce the representative pairs of FRET probes developed thus far. The efficiency of FRET is depending on the spectral overlap of donor emission and acceptor abso...

A novel mesoporous nanocarrier consisting of a silver core, a silica spacer with controlled thickness and a fluorophores-loaded mesoporous silica shell was fabricated for the metal-enhanced fluorescence (MEF) and Förster resonance energy transfer (FRET) effects.

Newly-synthesized amphiphilic carbon dots were used for spectroscopic analysis and multicolour microscopic imaging of membranes and live cells. We show that Förster resonance energy transfer (FRET) occurred from the amphiphilic carbon dots to different membrane-associated fluorescence acceptors. The amphiphilic carbon dots enabled imaging of membrane disruption by the beta-amyloid peptide.

Ras is a signaling protein involved in a variety of cellular processes. Hence, studying Ras signaling with high spatiotemporal resolution is crucial to understanding the roles of Ras in many important cellular functions. Previously, fluorescence lifetime imaging (FLIM) of fluorescent resonance energy transfer (FRET)-based Ras activity sensors, FRas and FRas-F, have been demonstrated to be usefu...