Search

A commercially available naphthalene fluorophore serves as a ratiometric indicator for albumin, showcasing its applications in albumin-based supramolecular recognition. [ABSTRACT FROM AUTHOR]

The first fluorescent sensor based on the indicator displacement assay (IDA) for on-site determination of etomidate. [ABSTRACT FROM AUTHOR]

Intermolecular proton transfer from a flavonol-based probe to the arginine (Arg222) in drug site 1 of human serum albumin triggers an unusual red-shifted ratiometric fluorescence response, which can be applied in the point-to-care diagnosis of hypoalbuminemia. [ABSTRACT FROM AUTHOR]

Biomarkers are essential in biology, physiology, and pharmacology; thus, their detection is of extensive importance. Fluorescent probes provide effective tools for detecting biomarkers exactly. Excited state intramolecular proton transfer (ESIPT), one of the significant photophysical processes that possesses specific photoisomerization between Keto and Enol forms, can effectively avoid annoying interference from the background with a large Stokes shift. Hence, ESIPT is an excellent choice for biomarker monitoring. Based on the ESIPT process, abundant probes were designed and synthesized using three major design methods. In this review, we conclude probes for 14 kinds of biomarkers based on ESIPT explored in the past five years, summarize these general design methods, and highlight their application for biomarker detection in vitro or in vivo. [ABSTRACT FROM AUTHOR]

Two new cyanine-based fluorescent probes 1 and 2 have been developed. Probe 1 bears two cyanine units in a single molecule, and probe 2 contains a bis(trifluoromethyl)benzenethiol moiety. Both are non-fluorescent. The addition of intracellular glutathione (GSH) significantly enhanced the NIR fluorescence of the two probes. Both probes were used to image varying amounts of GSH in living cells. In tumor bearing mice, the in vivo fluorescence intensity of both probes was higher in tumors, where GSH is overexpressed, than in normal tissues. These results suggest that these new fluorogenic probes have potential for GSH-targeting diagnostic imaging. [ABSTRACT FROM AUTHOR]

Polydiacetylenes (PDAs) have received increasing attention as smart materials owing to their unique properties. Upon addition of various stimuli, blue PDAs can undergo a colorimetric transition from blue to red along with a change from non-fluorescent to fluorescent. The optical changes can be readily detected by the naked eye and by using absorption and fluorescence spectrometers. These properties make PDAs excellent materials for use in platforms for sensing chemical or biological targets. In recent years, a number of biosensors and chemosensors based on the optical responses of polydiacetylenes have been reported. In this review, recent advances made in this area were discussed following a format based on different cognizing targets, including temperature, metal ions, anions, surfactants, amines, water, gas, sugars, hydrocarbons, neomycin, heparin, virus, enzymes, bacteria, and cancers. Emphasis is given to the methods used to prepare PDA sensing systems as well as their sensing performance. [ABSTRACT FROM AUTHOR]

Reactive oxygen (ROS) and nitrogen (RNS) species cause oxidative and nitrosative stresses, respectively. These stresses are implicated not only in diverse physiological processes but also in various pathological processes, including cancer and neurodegenerative disorders. In addition, some ROS and RNS in the environment are pollutants that threaten human health. As a consequence of these effects, sensitive methods, which can be employed to selectively monitor ROS and RNS in live cells, tissues and organisms as well as in environmental samples, are needed so that their biological roles can be understood and their concentrations in environmental samples can be determined. In this review, fluorescent, luminescent and colorimetric ROS and RNS probes, which have been developed since 2011, are comprehensively discussed. [ABSTRACT FROM AUTHOR]

A novel naphthalimide-based fluorescent probe employing a sulfonamide unit as a thiol-responsive group is reported. It is capable of efficiently distinguishing GSH from cysteine and homocysteine. Bioimaging shows that it has high selectivity in living cells and can visualize the level of GSH in lysosomes. It is worth mentioning that different groups on the imide unit can affect the selectivity and reaction dynamics of the probe towards thiols. [ABSTRACT FROM AUTHOR]

Plasmonics have been proven to be an effective way to harness more incident light to achieve high efficiency in photovoltaic devices. Herein, we explore the possibility that plasmonics can be utilized to enhance light trapping and power conversion efficiency (PCE) for polymer–quantum dot (QD) hybrid solar cells (HSCs). Based on a low band-gap polymer poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b′]-dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) and a CdSe QD bulk-heterojunction (BHJ) system, gold nanoparticles were doped at different locations of the devices. Successfully, an improved PCE of 3.20 ± 0.22% and 3.16 ± 0.15% was achieved by doping the hole transporting layer and the active layer, respectively, which are among the highest values reported for CdSe QD based HSCs. A detailed study of processing, characterization, microscopy, and device fabrication is conducted to understand the underlying mechanism for the enhanced device performance. The success of this work provides a simple and generally applicable approach to enhance light harnessing of polymer–QD hybrid solar cells. [ABSTRACT FROM AUTHOR]

Different approaches have been used in developing new coronary stents to protect against thrombosis and minimize restenosis. Here we describe a new zwitterionic bare metal stent (BMS) surface based on 2-((bromobutyryl)oxy)ethyl acrylate (BBEA) hyperbranched polymer. The new BMS produced was studied for its blood compatibility. The hemocompatibility studied including platelet adhesion tests, hemolysis assay, morphological changes of red blood cells (RBCs), coagulation time tests, plasma recalcification time (PRT) assay, complement activation, and platelet activation at the molecular level. Moreover the cytotoxicity of BMS before and after modification was also characterized by MTT assays. Most assays had remarkable differences in the presence of the new zwitterionic BMS, indicating the importance of the zwitterion. [ABSTRACT FROM AUTHOR]

We prepared antireflective nanoporous membranes by an extremely simple method which only involves the immersion of the optical substrates coated with amphiphilic block copolymers in hot ethanol for hours and a subsequent air drying process. Nanometer-sized pores were formed throughout the copolymer films through the swelling-induced pore generation mechanism. The pore structure and size, and consequently the antireflective properties of the porous copolymer membranes, could be modulated by changing the concentrations of the copolymer solutions and also the swelling temperature and time. A transmittance higher than 99% of the copolymer-coated glass substrate could be obtained at optimized conditions. Furthermore, to obtain robust and easily cleanable antireflective layers, we deposited TiO2 on the porous copolymer membranes by atomic layer deposition followed by calcination in air to burn off the polymer components, producing highly porous TiO2 membranes composed of interconnected nanotubes with thin tube walls. The replicated TiO2 membranes also displayed a good antireflective function because of their high porosity. Thanks to the conformal deposition of TiO2 on the copolymer membranes, the TiO2 replicas maintained structural integrity and mechanical robustness after high temperature calcination, and were tightly adhered to the glass substrate. Moreover, the calcined TiO2 was transformed to anatase and exhibited a photocatalytic effect. We demonstrated that contaminated TiO2 layers could recover their original high transmittance, either by directly rinsing with water or organic solvents, or by UV exposure to degrade organic contaminants. [ABSTRACT FROM AUTHOR]

Correction for 'Blood compatibility of a new zwitterionic bare metal stent with hyperbranched polymer brushes' by Xiaobo Wang et al., J. Mater. Chem. B, 2013, 1, 5036–5044, DOI: 10.1039/C3TB20855A. [ABSTRACT FROM AUTHOR]

In the past few decades, the development of optical probes for thiols has attracted great attention because of the biological importance of the thiol-containing molecules such as cysteine (Cys), homocysteine (Hcy), and glutathione (GSH). This tutorial review focuses on various thiol detection methods based on luminescent or colorimetric spectrophotometry published during the period 2010–2012. The discussion covers a diversity of sensing mechanisms such as Michael addition, cyclization with aldehydes, conjugate addition–cyclization, cleavage of sulfonamide and sulfonate esters, thiol–halogen nucleophilic substitution, disulfide exchange, native chemical ligation (NCL), metal complex-displace coordination, and nanomaterial-related and DNA-based chemosensors. [ABSTRACT FROM AUTHOR]

Polydiacetylenes (PDAs), a family of conjugated polymers, are known to show stimulus-induced apparent blue-to-red transitions, which have led to the development of a variety of PDA-based chemosensors. However, in most cases, recognition sites were introduced at the terminal ends of PDAs, therefore, recognition processes on the surface of PDAs have been the primary stimulations to induce blue to red colorimetric changes. In this study, we reported that diverse colorimetric changes can be observed for PDA based sensors in which penetration of cationic surfactant into PDAs bearing benzoic acid groups can cause not only the typical blue to red change but also blue to violet, blue to yellow or blue to orange color change. We systematically demonstrated that these novel findings can be used effectively to discriminate different cationic surfactants by using three different PDAs. Furthermore, theoretical calculations and transmission electron microscope (TEM) images also confirm these unique colorimetric changes. These results suggest a new direction in which to design colorimetric sensors based on PDA polymers. [ABSTRACT FROM AUTHOR]

Oxidative and nitrosative stress induced by ROS/RNS play crucial roles in a wide range of physiological processes and are also implicated in various diseases, including cancer and neurodegenerative disorders. Sensitive and selective methods for the detection of ROS/RNS based on fluorescent and luminescent probes are of great use in monitoring the in vivoproduction of these species and elucidating their biological functions. This critical reviewhighlights recent advances that have been made in the development of fluorescent and luminescent probes employed to monitor various ROS/RNS (132 references). [ABSTRACT FROM AUTHOR]

Fluorescent probes have been used extensively to monitor biomolecules and biologically relevant species in vitroand in vivo. A new trend in this area that has been stimulated by the desire to obtain more detailed information about the biological effects of analytes is the change from live cell to whole animal fluorescent imaging. Zebrafish has received great attention for live vertebrate imaging due to several noticeable advantages. In this tutorial review, recent advances in live zebrafish imaging using fluorescent probes, such as fluorescent proteins, synthetic fluorescent dyes and quantum dots, are highlighted. [ABSTRACT FROM AUTHOR]

This tutorial reviewfocuses on recent developments arising from studies of optical sensors for cyanide ions, which are categorized by approaches involving cyanide selective receptors, the utilization of metal coordinated complexes, and chemodosimeters. [ABSTRACT FROM AUTHOR]

Correction for 'Optical and electrical effects of plasmonic nanoparticles in high-efficiency hybrid solar cells' by Wei-Fei Fu et al., Phys. Chem. Chem. Phys., 2013, 15, 17105–17111, DOI: 10.1039/C3CP52723A. [ABSTRACT FROM AUTHOR]

A new NIR fluorescent sensor based on an amine-substituted heptamethine cyanine dye displayed a highly selective fluorescence enhancement with cyanide in aqueous solutions, and was applied for the imaging of anthropogenic and biogenic cyanide. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) is considered as the third signaling molecule in vivo and it plays an important role in various physiological processes and pathological processes in vivo, such as vasodilation, apoptosis, neurotransmission, ischemia/reperfusion-induced injury, insulin secretion and inflammation. Developing a highly selective and sensitive method that can detect H2S in the biological system is very important. In this work, a colorimetric and "turn-on" fluorescent probe is developed. Furthermore, this probe displays a highly selective response to H2S in aqueous solution and possesses good capability for bioimaging H2S without interference in living cells. The results suggest that a H2S-selective probe has good water-solubility, biocompatibility and cell-penetrability and can serve as an efficient tool for probing H2S in the cell level.

Response surface methodology based on a central composite rotatable design has been successfully used to model and optimize biochemical and biotechnological processes. Heat treatment could have an effect on beta-lactoglobulin (β-Lg) and lead to allergic reaction. To reduce this phenomenon, liposomes were used as carriers in this research. The mass ratio of phosphatidylcholine and cholesterol (2.5-12.5), β-Lg concentration (2.5-12.5 mg mL(-1)), sonication time (5-25, min) and temperature (25-40 °C) were selected as independent variables with encapsulation efficiency as a dependent variable. For each response, a second-order polynomial model was developed using multiple linear regression analysis. Applying a desirability function method the optimum parameters were: phosphatidylcholine to cholesterol ratio of 8.05, β-Lg concentration of 9.09 mg mL(-1), sonication time of 17.71 min and temperature of 30 °C. The particle size and encapsulation efficiency were found to be 189 nm and 61.55%, respectively. Furthermore, the in vitro stability of β-Lg nano-liposomes in simulated gastrointestinal juice was evaluated. The nano-liposomes showed an acceptable stability in simulated gastrointestinal juice at 37 °C for 4 h.

Recent advances in micro- and nanotechnology have provided a variety of particles with highly controlled shapes, sizes, chemical composition, and interesting properties. In this work, a novel kind of heparin-functionalized polyurethane microsphere (Hep-PU MS) was synthesized by a single-step phase separation method. The blood compatibility and anticoagulant effect of the Hep-PU MSs were investigated using coagulation tests, hemolysis assay, complement and platelet activation detection, cytotoxicity analysis, and drug loading and release study. The results confirmed that the heparin can substantially enhance the anticoagulant properties of PU MSs, and the Hep-PU MSs have the potential to be used as a mild anticoagulant compared to heparin. With the simplicity of the functionalized method, the excellent hemocompatibility and the slow-release of heparin, the Hep-PU MSs with desirable bioproperties can be readily tailored to cater to various biomedical applications.

A fluorescent probe based on fluorescein displays excellent selectivity and sensitivity for cysteine and its application for bio-imaging is described.

A specific and sensitive fluorescence-based method was developed for the imaging of microbe-induced HOCl production. Furthermore, we demonstrate dual oxidase (DUOX)-mediated HOCl generation in the mucosa of live animals providing a novel insight into mucosal innate immunity., (© The Royal Society of Chemistry 2011)

In this paper, we report new rhodamine hydrazone derivatives bearing thiol and carboxylic acid groups as selective fluorescent and colorimetric chemosensors for Hg(2+). The ring-opening process of spirolactam enables the large fluorescent enhancement and colorimetric change upon the addition of Hg(2+). The sample containing Hg(2+) was mixed with one of the chemosensors in a microchannel where the sensor was examined using confocal laser scanning microscopy. A plot of the fluorescent intensities of both chemosensors versus the log concentration of Hg(2+) exhibited a linear response (r(2)=0.95) in the range of 1 nM-1 μM, and the detection limits were 1 nM and 4.2 nM, respectively. Both chemosensors also enable the visualization of Hg(2+) accumulated in the nematode Caenorhabditis elegans previously exposed to nanomolar concentrations of Hg(2+)., (© The Royal Society of Chemistry 2011)

A fluorescent probe based on fluorescein displays an excellent selectivity and sensitivity for thiols and its application for bioimaging is described.

The first "Off-On" type fluorescent probe for Au3+ is reported, in which rhodamine-alkyne derivative displayed highly selective fluorescence enhancement and "naked-eye" detection upon the addition of Au3+ at pH 7.4.

The polydiacetylenes derived from a hydroxybenzaldehyde substituted diacetylene monomer display a unique colorimetric change (blue to red) and large fluorescent enhancement in the presence of cetyl trimethylammonium salt.