chemical, biochemical, and even biological species ( Figure 1 ). Furthermore, their distinctive near-infrared (NIR) optical response can be quantitatively interpreted [ 14,15 ] so that these redox processes can be tracked with single-electron sensitivity. To demonstrate their exciting new properties in interrogating complex redox systems, we use them to quantify chemically driven charge transfer across the electrifi ed cell membranes of Shewanella oneidensis MR-1, requiring only a simple optical readout and absent any external electrodes. Results and DiscussionRecently, it was shown that the characteristic wavelength and intensity of the NIR plasmon resonance absorption of tin-doped indium oxide (ITO) nanocrystals bound to an electrode can be strongly modulated in a reversible manner using a directional voltage bias. [ 9,16 ] These changes arise from the dependence of the Electron transfer in complex aqueous systems can be observed remotely with single-electron sensitivity using locally dispersed nanostructures conferred with electronic charge concentration-dependent plasmonic properties. When introduced to a system out of redox equilibrium, tin-doped indium oxide nanocrystals undergo rapid multielectron transfer until redox equilibrium is reached; this modulates their free carrier concentration and plasmonic optical properties in the spectrally isolated near-infrared. This capability is harnessed here to noninvasively track, model, and quantify electron transfer events reversibly for organic, inorganic, biogenic, and even living cells.Adv. Optical Mater. 2015, 3, 1293-1300 www.MaterialsViews.com www.advopticalmat.de Figure 1. Plasmonic doped metal oxide nanocrystals reversibly exchange electrons with redox-active small molecules, biomacromolecules, and live bacteria. These multi-electron exchanges modulate their free-carrier concentration, thus changing their plasmonic optical properties. This redoxresponsive plasmon absorbance can be modeled to provide quantitative analysis of electron transfer in systems out of redox equilibrium. wileyonlinelibrary.com

Water‐dispersible, polymer‐wrapped nanocrystals are highly sought after for use in biology and chemistry, from nanomedicine to catalysis. The hydrophobicity of their native ligand shell, however, is a significant barrier to their aqueous transfer as single particles. Ligand exchange with hydrophilic small molecules or, alternatively, wrapping over native ligands with amphiphilic polymers is widely employed for aqueous transfer; however, purification can be quite cumbersome. We report here a general two‐step method whereby reactive stripping of native ligands is first carried out using trialkyloxonium salts to reveal a bare nanocrystal surface. This is followed by chemically directed immobilization of a hydrophilic polymer coating. Polyacrylic acids, with side‐chain grafts or functional end groups, were found to be extremely versatile in this regard. The resulting polymer‐wrapped nanocrystal dispersions retained much of the compact size of their bare nanocrystal precursors, highlighting the unique role of monomer side‐chain functionality to serve as effective, conformal ligation motifs. As such, they are well poised for applications where tailored chemical functionality at the nanocrystal's periphery or improved access to their surfaces is desirable. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

This work demonstrates a green method for the encapsulation of a natural phase change material (PCM), lauric acid (LA), in polystyrene (PS) hollow fibers through a solvent-assisted diffusion process inside fiber nanochannels. The obtained LAPS composite fibers had a melting enthalpy of up to 147.8 J/g, which was 82.0% the heat storage capacity of pristine LA (180.2 J/g). This capacity was higher than the values (generally less than 60%) reported in the literature. The LA content in the composite fibers could be controlled by the solution concentration and the solvent. On the contrary, encapsulation time had little effect on the final LA loading beyond 1 h due to the rapid diffusion of the LA solution. The optimal LA loading (82.2%) was achieved in 0.4 g/mL LA ethanol solution for 1 h, which was more than 4 times the weight of PS fibers. Simultaneous TGA−DSC, ATR, Raman, and SEM measurements confirmed the homogeneous distribution of LA inside the fibers across the whole membranes. Further, the LAPS composite fibers showed a long-lasting stability during cycling without storage capacity deterioration, as well as an exceptional structural stability without LA leaking and fiber rupture during 100 heating−cooling cycles. The energy-dense and form-stable LAPS composite fibers have a great potential for various thermal energy storage applications like "temperature-smart" buildings and textiles.

Blue rubber bleb nevus syndrome (BRBNS) commonly presents with anemia from bleeding gastrointestinal (GI) vascular malformations. Management is highly variable, as no consensus guidelines for medical treatment currently exist. Sirolimus has been used in BRBNS to decrease GI bleeding and seems well tolerated, though questions remain regarding dosing, duration of therapy, and adverse effects. Here, we report our single‐center experience of four pediatric patients with BRBNS who were successfully treated with sirolimus and review the existing literature regarding sirolimus for treatment of GI bleeding in BRBNS. Further prospective studies are needed to establish optimal dosage, drug monitoring, and duration.