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Hydrazine (N 2 H 4) and hypochlorite (ClO−) are extremely harmful to the public health, so it is vitally necessary to detect them in living system. Herein, we developed a new phenthiazine-thiobarbituric acid based dual-analyte responsive fluorescent sensor PT for visually distinguishing and detecting N 2 H 4 and ClO−. PT underwent N 2 H 4 /ClO−-induced C C breakage, achieving olive-drab/brilliant green fluorescence lighting-up response towards N 2 H 4 /ClO− with superb specifity, ultra-sensitivity (detection limit: 15.4 nM for N 2 H 4 , 13.7 nM for ClO−), and ultra-fast response (N 2 H 4 : <15 s, ClO−: <20 s). The mechanisms for sensing N 2 H 4 and ClO− were investigated with support of spectral measurements and DFT investigation. Sensor based paper-strip/silica-gel device was developed for in-field supervision and on-site monitoring of gaseous and aqueous N 2 H 4 and ClO− solution. In addition, the PT was also applied for quantitatively detecting N 2 H 4 and ClO− in soil, food, plants and bio-fluids. Moreover, PT was utilized to visualize exogenous N 2 H 4 and ClO− in living plants and live-cells, demonstrating this sensor utilized as a powerful tool to detect N 2 H 4 and ClO− in biological fields. [Display omitted] • A new dual-analyte fluorescent sensor PT was reported for rapid and simultaneous detecting N 2 H 4 and ClO−. • The sensing system presented superb specificity, ultra-sensitivity, ultra-rapid response and excellent bio-compatibility. • PT was utilized in colorimetric detection of ClO− as well as gaseous and aqueous N 2 H 4. • PT was capable to sensitively detect and bioimage N2H4 and ClO– in biofluids, live-cells, and plants. [ABSTRACT FROM AUTHOR]

Excessive levels of cyanide (CN−) and hypochlorite (ClO−) anions are the significant threats to the human health and the environment. Thus, great efforts have been to design and synthesize molecular sensors for the simple, instantaneous and efficient detecting environmentally and biologically important anions. Currently, developing a single molecular sensor for multi-analyte sensing is still a challenging task. In our present work, we developed a new molecular sensor (3TM) based on oligothiophene and Meldrum's acid units for detecting cyanide and hypochlorite anions in biological, environmental and food samples. The detecting ability of 3TM has been examined to various testing substances containing amino acids, reactive oxygen species, cations and anions, showing its high selectivity, excellent sensitivity, short response time (ClO−: 30 s, CN−: 100 s), and broad pH working range (4–10). The detection limits were calculated as 4.2 nM for ClO− in DMSO/H 2 O (1/8, v/v) solution and 6.5 nM for CN− in DMSO/H 2 O (1/99, v/v) solution. Sensor 3TM displayed sharp turn-on fluorescence increasement (555 nm, 435 nm) and sensitive fluorescence color changes caused by CN−/ClO−, which is ascribed to the nucleophilic addition and oxidation of ethylenic linkage by cyanide and hypochlorite, respectively. Moreover, sensor 3TM was applied for hypochlorite and cyanide detecting in real-world water, food samples and bio-imaging in live cells and zebrafish. To our knowledge, the developed 3TM sensor is the seventh single-molecular sensor for simultaneous and discriminative detecting hypochlorite and cyanide in food, biological and aqueous environments using two distinct sensing modes. [Display omitted] • A new dual-responsive fluorescent sensor 3TM was developed for simultaneous and discriminative detecting ClO− and CN−. • Sensor 3TM for fluorescence turn-on detection of ClO− and CN− with high specificity and rapid response. • Sensor 3TM for nano-level detection of ClO− and CN− with extremely low detection limits (ClO−: 4.2 nM, CN−: 6.5 nM). • Sensor 3TM was utilized to effectively detect ClO− and CN− in real-world water and food samples. • Sensor 3TM was applied for real-time tracking ClO− and CN− levels in live cells and zebrafish. [ABSTRACT FROM AUTHOR]

Rationally designed and effectively synthesized D-π-A chemosensor DTA containing bithiophene fluorophore by using bithiophene aldehyde and benzothiazole salt and serves as highly specific chemosensor for colorimetric/fluorimetric turn-on detection of hypochlorite (ClO−) in ∼100 % aqueous media. DTA has obvious advantages of high specificity, short response time (8 s), broad pH working scope, ultra-sensitivity with low detection limit (5.3 nM), good bio-compatibility and permeability. The responding mechanism of DTA toward ClO− was investigated by 1H NMR, FTIR, HRMS, optical spectra and DFT calculations. Interestingly, DTA coated silica-gel, cotton buds, and filter-paper test strips were developed for qualitative and quantitative visual detection of ClO− in real-time. Notably, DTA was utilized to quantitatively detect ClO− in real-water and bio-fluids. Moreover, DTA was also applied to bioimage ClO− in live-cells, zebrafish and plant kingdoms, highlighting its broad application potentials. The simple structure and versatility of the DTA provides a convenient approach for developing multi-functional sensors and expanding its broader application fields. [Display omitted] • A new bithiophene-benzothiazole-based colorimetric and fluorescent turn-on sensor DTA was reported for detecting ClO−. • The sensing system displays attractive advantages of ultra-rapidity, ultra-sensitivity and bio-compatibility. • DTA -based colorimetric sensing system was utilized for fast, visual and real-time detecting ClO−. • DTA can sensitively detect trace ClO− in real-water and bio-fluids. • DTA was applied to bio-image ClO− in living cells, zebrafish and plants. [ABSTRACT FROM AUTHOR]

A new ICT type D-π-A structured chemosensor DTB derived from a bithiophene-benzothiazole derivative has been synthesized. Sensor DTB showed a colorimetric and fluorometric dual-signaling response to hypochlorite (ClO−) in EtOH/HEPES solution (1/99, V/V, pH = 7.4, nearly 100% aqueous solution). Sensor DTB exhibited well specificity, high sensitivity and rapidity (<1 min) for ClO− with a detection limit of 25 nM. Sensor DTB features remarkable color changes and significant fluorescence "turn-on" response (ca. 45 fold) after treating with ClO−. Comprehensive analyses by 1H NMR, TLC, FTIR, HRMS, UV–vis, fluorescence and DFT illustrated that ClO− reacted with the C C bond of DTB , generating fluorophore 2T-CHO , leading to strong blue fluorescence. Interestingly, DTB loaded colorimetric test strips were established for rapid and real-time visual detection of ClO−. Furthermore, the DTB was successfully applied to quantitatively and sensitively detect ClO− in 84 disinfectant, bio-fluids (human serum and urine) and actual water samples. Importantly, the biocompatible DTB has been employed for visualizing and bioimaging ClO− in mung bean sprouts, Arabidopsis, live cells and zebrafish. These investigations demonstrate that DTB has great potentials for detecting ClO− in various biosystems and environments. This work would offer a new idea for developing multifunctional sensors with better performance for chemo/biosensors. [Display omitted] • A new colorimetric/fluorescent turn-on sensor DTB was developed for specific, sensitive and fast detection of ClO−. • Colorimetric sensing platform based on DTB was applied for specifically and rapidly detecting ClO− in real-time. • DTB could effectively detect ClO− in real-water, 84 liquid disinfectant and bio-fluids. • Biocompatible DTB was capable of bio-imaging ClO− in plants, living cells and zebrafish. [ABSTRACT FROM AUTHOR]

• Novel phenothiazine-based colorimetric and ratiometric fluorescent sensor PPM for Hg2+ is synthesized. • PPM shows high selectivity and low detection limit of 12.5 nM in a wide pH range. • The response time of PPM for Hg2+ is within 1 min and suitable for ultrafast detection of Hg2+. • PPM for Hg2+ shows good applicability for paper/TLC-based "naked-eye" colorimetric assay. • PPM was used for fluorescence imaging of Hg2+ in living cells. A new phenothiazine-based sensor PPM was successfully designed and synthesized, which shows highly selective, ultrafast, naked-eye colorimetric and turn-on ratiometric fluorescence sensing of Hg2+ on the basis of the ICT from phenothiazine to aldehyde. Upon addition of Hg2+, obvious blue fluorescence at 455 nm decreased while green fluorescence at 528 nm enhanced, which exhibits ratiometric fluorescent turn-on response along with a "naked-eye" color change from pale-blue to bright-green. The PPM for highly sensing of Hg2+ with a quite low detection limit (12.5 nM) and a wide pH application range. The sensing mechanism proved to be the Hg2+-triggered thioacetal deprotection reaction was confirmed. Importantly, PPM was successfully employed for highly selective detecting and imaging of Hg2+ in living cells, as well as on paper/TLC-based "naked-eye" colorimetric assay. [ABSTRACT FROM AUTHOR]

In this study, a new phenomena-Meldrum's acid D-π-A fluorescent sensor 5-((10-(2-ethoxyethyl)−10H-phenoxazin-3-yl)methylene)−2,2-dimethyl-1,3-dioxane-4,6-dione (PM) was developed, which was employed for colorimetric and turn-on fluorimetric sensing hydrazine in ~100% aqueous media. The sensor PM towards hydrazine shows excellent selectivity with strong anti-interference capability, high sensitivity with extremely low detection limit of 4.2 nM, ultra-rapid response (15 s) and broad pH application range (5−9). The proposed mechanism of sensor PM for sensing hydrazine was supported by 1H NMR, FTIR, HRMS analyses and fluorescence titration studies. The sensor PM not only provides an effective tool for quick and on-site detecting gaseous and aqueous N 2 H 4 in paper strips with sensitive naked-eye color diversification, but also is capable of quantitatively and sensitively detecting trace levels of N 2 H 4 in environmental, biological, plant and food samples. More importantly, the sensor PM was successfully utilized for bio-imaging of N 2 H 4 in plants and animals. As expected, the hydrazine-sensing method in this work is of great significance for further biological applications. [Display omitted] • A new phenoxazine-based D-π-A colorimetric and fluorescent turn-on sensor PM was reported for hydrazine sensing. • The detecting system shows atattractive features of ultra-sensitivity, ultra-rapidity, and functional compatibility. • PM -coated paper was used for visual, rapid and real-time detecting gaseous and aqueous N 2 H 4. • PM can effectively monitor trace N 2 H 4 in environmental, biological, plant and food samples. • PM was successfully applied to bio-imaging N 2 H 4 in plant and zebrafish. [ABSTRACT FROM AUTHOR]

Abstract: We have developed a one-dimensional position-sensitive detector (1-D PSD) for X-ray backscatter imaging which had a scintillator–fiber- position-sensitive photomultiplier (PSPMT) structure. Scintillators of the detector were covered by diffused reflection material. Teflon and the fiber of the detector was covered by mirror reflection material an aluminum foil. The detector was composed of a 1×25 LYSO array which was coupled with 25 plastic fibers. Another end of these fibers was twisted into a 5×5 array and coupled with a PSPMT R8520. The detector element''s area was 4.2×20mm2 and the position resolution was 4.2mm. We tested the positioning histogram of the detector set up an X-ray backscatter imaging system, and obtained an X-ray backscatter image from it. [Copyright &y& Elsevier]

A new bithiophene-based biocompatible fluorescent and colorimetric sensor 2TD capable of detecting hypochlorite (ClO−) in enviro/biosystem was successfully synthesized. This sensor 2TD underwent a highly specific and sensitive oxidation reaction with ClO− and produced a bithiophene aldehyde (2T-CHO) emitting strong blue fluorescence, which was strongly confirmed by 1H NMR, HRMS, FTIR and DFT calculation. The 2TD for detecting ClO− displays an ultra-fast response (25 s), great water-solubility (~100% aqueous solution), wide pH working range (7–11), excellent anti-interference capability, and ultra-sensitivity with low detection limit of 8.3 nM. Colorimetric test strips demonstrate that 2TD can be utilized as a cost-effective and efficient solid-state sensor for rapidly and conveniently sensing ClO− with great sensitivity in practical applications. With the robust applicability, the 2TD was successfully utilized to determine/image ClO− in environmental water and live-cells. More interestingly, this developed sensor 2TD could be used as an efficient test tool for ClO− sensing. Unlabelled Image • A novel selective fluorescent sensor 2TD for ClO− was developed. • 2TD showed great water solubility, ultrafast response, ultrasensitive detection and wide pH range in applications. • 2TD was applied to detect/image ClO− in real water samples and HeLa cells. • 2TD served as good fluorescent display material and efficient ClO− test tool. [ABSTRACT FROM AUTHOR]

• Novel phenothiazine-based colori/fluorimetric sensor PN was developed. • PN showed "naked-eye" colorimetric and "turn-off" fluorescence response for Cu2+. • PN for Cu2+ recognition with ultrafast response, great sensitivity and good reversiblity. • PN served as a cost-effective solid-state sensor for convenient detection of Cu2+. • PN can monitor Cu2+ in water samples with good accuracy and high precision. A novel highly sensitive and selective phenothiazine-based sensor PN has been successfully synthesized. The sensor PN showed specific recognition towards Cu2+ through dual "naked-eye" colorimetric and "turn-off" fluorescence responses in DMSO/H 2 O (1:3, V/V) solution with ultrafast response and good reversibility. The detection limit was determined to be as low as 0.179 µM, which was much lower than drinking water permission concentration by the United States Environmental Protection Agency (～20 µM) and the World Health Organization (～30 µM). The 1:1 binding mechanism of PN with Cu2+ was proposed and well confirmed by fluorescence titration, Job's plot, 1H NMR, HRMS, FTIR analysis and DFT studies. Moreover, the sensor PN was successfully applied to sensitively detect the Cu2+ ions in real water samples with good accuracy and high precision. Furthermore, sensor PN could serve as a cost-effective solid-state sensor for immediate, convenient and "naked-eye" colorimetric detection of Cu2+ in environmental samples. [ABSTRACT FROM AUTHOR]