Search

Energy saving is a global topic of critical importance. Electrochromic devices (ECDs) could be used to control energy flow by modulating the light absorption reversibly upon application of a small potential bias. Herein, a visible‐NIR dual‐band ECD based on the viologen analogue 4, 4′‐(thiophene‐2, 5‐diyl) bis(1‐methylpyridin‐1‐ium) diiodide (TMP) was assembled with a simple all‐in‐one configuration. The TMP‐based gel ECD possesses high dynamic contrast (81.7 % at 570 nm, 68.6 % at 835 nm, 62.8 % at 910 nm and 55.3 % at 1046 nm), excellent cyclic stability (70.6 % of ▵T at 570 nm maintained after 25000 cycles at 1.4 V), and low power consumption (15.2 mJ/cm2 to complete the coloring process, 2.5 mW/cm2 to keep color and low transmittance). Remarkably, the absorption of visible and NIR light could be selectively adjusted by varying the coloring time. For comparison, a dimethyl viologen (DMV)‐based gel ECD was fabricated, and the SAR (structure‐activity relationship) was established by cyclic voltammetry, density functional theory (DFT) calculations, and other electrochromic performance parameters. [ABSTRACT FROM AUTHOR]

Regulation of intracellular potassium (K+) concentration plays a key role in metabolic processes. So far, only a few intracellular K+ sensors have been developed. The highly selective fluorescent K+ sensor KS6 for monitoring K+ ion dynamics in mitochondria was produced by coupling triphenylphosphonium, borondipyrromethene (BODIPY), and triazacryptand (TAC). KS6 shows a good response to K+ in the range 30-500 m M, a large dynamic range ( Fmax/ F0≈130), high brightness ( ϕf=14.4 % at 150 m M of K+), and insensitivity to both pH in the range 5.5-9.0 and other metal ions under physiological conditions. Colocalization tests of KS6 with MitoTracker Green confirmed its predominant localization in the mitochondria of HeLa and U87MG cells. K+ efflux/influx in the mitochondria was observed upon stimulation with ionophores, nigericin, or ionomycin. KS6 is thus a highly selective semiquantitative K+ sensor suitable for the study of mitochondrial potassium flux in live cells. [ABSTRACT FROM AUTHOR]

A series of new poly[ N-(2-hydroxypropyl)methacrylamide]-based amphiphilic copolymers were synthesized through a radical copolymerization of a monomeric/hydrophobic fluorophore possessing aggregation-induced emission (AIE) properties with N-(2-hydroxypropyl)methacrylamide. Photophysical properties were investigated using UV-Vis absorbance and fluorescence spectrophotometry. Influences of the polymer structures with different molar ratios of the AIE fluorophores on their photophysical properties were studied. Results show that the AIE fluorophores aggregate in the cores of the micelles formed from the amphiphilic random copolymers and polymers with more hydrophobic AIE fluorophores facilitate stronger aggregations of the AIE segments to obtain higher quantum efficiencies. The polymers reported herein have good water solubility, enabling the application of hydrophobic AIE materials in biological conditions. The polymers were endocytosed by two experimental cell lines, human brain glioblastoma U87MG cells and human esophagus premalignant CP-A, with a distribution into the cytoplasm. The polymers are noncytotoxic to the two cell lines at a polymer concentration of 1 mg/mL. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]