Supramolecular polymerization of BODIPY dyes extended with rationally designed pyrazole-based motifs

Two distinct aggregation pathways during the supramolecular polymerization of BODIPY dyes functionalized with rationally designed pyrazole-based motifs have been investigated.

Fluorescent-Based Thermal Sensing in Lipid Membranes

Thermal mapping in biological membranes could unlock and help us understand many chemical and physical processes that do not only pertain to localized membrane phenomena but also extend to many other intra- and extracellular pathways. In this manuscript, we report the development of a ratiometric thermal fluorescent probe based on the Förster resonance energy transfer between a lipid-embedded conjugated polyelectrolyte and a lyophilic acceptor dye. We showed that the Förster resonance energy transfer (FRET) pair is sensitive within the relevant physiological temperature window (20.0-50.0 °C). The signal was also shielded from an external pH and stable when cycled multiple times. The probe was also sensitive to the membrane composition and could, therefore, be further developed to probe the membrane composition and viscosity.

Localized catalysis driven by the induction heating of magnetic nanoparticles

Heat generated from magnetic nanoparticles when placed in an alternating magnetic field is used to drive a catalytic chemical reaction.

Fluorescent thermal sensing using conjugated polyelectrolytes in thin polymer films

Thermal sensing in thin films polymers has been a significant limitation towards optimizing the heat dissipation in micro- and nano-electronic devices as well as many other thin film-based technologies. In this work, we report on poly (phenylene ethynylene) fluorescent-based conjugated polyelectrolyte capable of detecting thermal fluctuations in polymer films prepared from polyvinylpyrrolidone-co-vinyl acetate. The sensor was first optimized in solution by testing two polyvinylpyrrolidone (PVP) copolymers (co-vinyl acetate (VA) and co-polystyrene (PS)) before it was spun cast onto quartz slides and imaged using a DSLR camera at different temperatures. The images were analyzed and showed a change in color with the increase in temperature. When not illuminated, the polymer thin film is clear and transparent.

Well-Optimized Conjugated GO-DNA Nanosystem for Sensitive Ratiometric pH Detection in Live Cells

Intracellular pH is a vital parameter which can reflect the physiological process, and the detection of intracellular pH with a high signal-to-noise ratio (SNR) remains a challenge. Compared to pH biosensors based on a single-wavelength signal, it is much easier to obtain better sensitivity and higher SNR from the biosensors by two-wavelength ratiometric signals. In this study, we used DNA-grafted graphene oxide (GO) to ratiometrically detect intracellular pH ranging from basic to acidic. A high SNR with a 35-fold difference in the ratiometric output has been achieved through careful optimization: (1) A high DNA conjugation yield of 45% has been gained through utilizing the partial double-stranded assembly strategy. (2) Herring sperm DNA (HSD) plays an important role in improving the sensitivity of the nanosystem by purifying and passivating the surface of GO; therefore, the concentration of HSD has been optimized to pursue the most sensitive ratiometric response. Apart from the ultrahigh SNR, fabricated GO-AR-Cy5/IFO-Cy3 exhibited excellent stability and biocompatibility in biological environments. Further experiments demonstrated that the nanosystem worked well in live cells in response to pH changes. It is possible to distinguish small pH differences and realize quantitative detection based on ratiometric fluorescence imaging by laser scanning confocal microscope analysis, which makes the nanosystem a promising candidate for further biological study and clinical applications.

Salt-induced thermochromism of a conjugated polyelectrolyte

We report here the photophysical properties of a water-soluble polythiophene with cationic side-chains in PBS buffer solution.

Tunable nanothermometer based on short poly(phenylene ethynylene)

We report a self-referencing ratiometric nanothermometer based on short conjugated polyelectrolytes (CPEs).