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https://www.readbyqxmd.com/read/30110410/a-multi-functional-chemosensor-for-highly-selective-ratiometric-fluorescent-detection-of-silver-i-ion-and-dual-turn-on-fluorescent-and-colorimetric-detection-of-sulfide
#1
Ji Hye Kang, Ju Byeong Chae, Cheal Kim
A multi-functional chemosensor 1 as silver and sulfide detector was synthesized by the combination of octopamine and 4-dimethylaminocinnamaldehyde. Sensor 1 exhibited a ratiometric fluorescence emission for Ag+ from blue to sky. The binding mode of 1 and Ag+ turned out to be a 1 : 1 ratio as determined using Job plot and electrospray ionization (ESI) mass spectral analyses. The sensing mechanism of 1 with silver ion was unravelled by 1 H NMR titrations and theoretical calculations. Sensor 1 also discerned sulfide by enhancing fluorescence intensity and changing colour from yellow to colourless in aqueous solution...
June 2018: Royal Society Open Science
https://www.readbyqxmd.com/read/30108730/cu-ii-ga-iii-and-in-iii-complexes-of-2-acetylpyridine-n-4-phenylthiosemicarbazone-synthesis-spectral-characterization-and-biological-activities
#2
Yu-Ting Wang, Yan Fang, Meng Zhao, Ming-Xue Li, Yu-Mei Ji, Qiu-Xia Han
In this paper, synthesis and characterization of metal complexes [Cu2 (L)3 ]ClO4 ( 1 ), [Ga(L)2 ]NO3 ·2H2 O ( 2 ) and [In(L)2 ]NO3 ·H2 O ( 3 ) (HL = 2-acetylpyridine N (4)-phenylthiosemicarbazone) was carried out, including elemental analysis, spectral analysis (IR, UV-vis, NMR), and X-ray crystallography. Complex 1 contains one S-bridged binuclear [Cu2 (L)3 ]+ unit, where two Cu atoms display diverse coordination geometries: one being square planar geometry and the other octahedral geometry. Both 2 and 3 are mononuclear complexes, and the metal centers in 2 and 3 are chelated by two NNS tridentate ligands possessing a distorted octahedral geometry...
November 1, 2017: MedChemComm
https://www.readbyqxmd.com/read/30106284/role-of-extracellular-polymeric-substances-in-a-methane-based-membrane-biofilm-reactor-reducing-vanadate
#3
Chun-Yu Lai, Qiu-Yi Dong, Jiaxian Chen, Quan-Song Zhu, Xin Yang, Wen-Da Chen, He-Ping Zhao, Liang Zhu
For the first time, we demonstrated vanadate (V(V)) reduction in a membrane biofilm reactor (MBfR) using CH4 as the sole electron donor. V(V)-reducing capability of the biofilm kept increasing, with complete removal of V(V) achieved when the influent surface loading of V(V) was 363 mg m-2 day-1. Almost all V(V) was reduced to V(IV) precipitates, which is confirmed by scanning electron microscope coupled to energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray photoelectron spectroscope (XPS). Microbial community analysis revealed that denitrifiers Methylomonas and Denitratisoma might be the main genera responsible for V(V) reduction...
August 14, 2018: Environmental Science & Technology
https://www.readbyqxmd.com/read/30106269/a-biocatalyst-and-colorimetric-fluorescent-dual-biosensors-of-h2o2-constructed-via-hemoglobin-cu3-po4-2-organic-inorganic-hybrid-nanoflowers
#4
Jiaojiao Gao, Hui Liu, Lingyan Pang, Kai Guo, Junqi Li
In this paper, the 3-dimensional Hemoglobin (Hb)-Cu3(PO4)2 organic/inorganic hybrid nanoflowers (Hb-Cu3(PO4)2 HNFs) self-assembled by nanopetals were synthesized via a facile one-pot green synthetic method. The compositions and microstructure of the Hb-Cu3(PO4)2 HNFs were well characterized with X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and UV-vis spectrometer, respectively. The as-prepared Hb-Cu3(PO4)2 HNFs to be used as an biocatalyst to constructed colorimetric/fluorescent dual biosensors...
August 14, 2018: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/30105545/reactive-blue-4-as-a-single-colorimetric-chemosensor-for-sequential-determination-of-multiple-analytes-with-different-optical-responses-in-aqueous-media-cu-2-cysteine-using-a-metal-ion-displacement-and-cu-2-arginine-through-the-host-guest-interaction
#5
Hossein Tavallali, Gohar Deilamy-Rad, Narges Mosallanejad
In the current study, we reported a novel label-free and facile colorimetric approach for the sequential detection of copper ion (Cu2+ ), L-arginine (Arg), and L-cysteine (Cys) in the H2 O (10.0 mmol L-1 HEPES buffer solution, pH 7.0) using Reactive Blue 4 (RB4). First, the presence of Cu2+ led to a naked-eye color and spectral changes according to the binding site-signaling subunit approach. Then, the RB4-Cu2+ complex was successfully applied for Cys and Arg through different recognition pathways. The optical signals for Arg were observed due to its association involving the amino group, as well as the participation of the carboxylate group in a bidentate form to the complex, while selective behavior for Cys was explained by a metal displacement mechanism...
August 13, 2018: Applied Biochemistry and Biotechnology
https://www.readbyqxmd.com/read/30104740/turn-off-colorimetric-sensor-for-sequence-specific-recognition-of-single-stranded-dna-based-upon-y-shaped-dna-structure
#6
Hong Zhang, Xintong Li, Fan He, Mingqin Zhao, Liansheng Ling
A novel turn-off colorimetric sensor for sequence-specific recognition of single-stranded DNA (ssDNA) was established by combining Y-shaped DNA duplex and G-quadruplex-hemin DNAzyme. A G-rich single-stranded DNA (Oligo-1) displays peroxidase mimicking catalytic activity due to the specific binding with hemin in the presence of K+ , which was able to catalyze the oxidation of colorless 2,2'-azinobis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS2- ) by H2 O2 to generate green ABTS•- radical for colorimetric assay...
August 13, 2018: Scientific Reports
https://www.readbyqxmd.com/read/30103821/foxp3-knockdown-inhibits-the-proliferation-and-reduces-notch1-expression-of-t-cell-acute-lymphoblastic-leukemia-cells
#7
Satoru Yonekura, Mai Itoh, Erika Shiratori, Mika Ohtaka, Shuji Tohda
OBJECTIVE: Forkhead box P3 (FOXP3) is a master transcriptional factor of regulatory T-cells (Tregs). Recent studies have shown that FOXP3 is associated with growth inhibition of cancer cells. However, the role of FOXP3 in acute T-lymphoblastic leukemia (T-ALL) cells is not known. It was also reported that NOTCH signaling promoted the expression of FOXP3 in Tregs. However, the effect of FOXP3 on NOTCH expression in T-ALL cells is little known. Therefore, we examined the effect of FOXP3 knockdown on the proliferation of T-ALL cells and NOTCH1 signaling...
August 13, 2018: BMC Research Notes
https://www.readbyqxmd.com/read/30102448/colorimetric-carbonyl-sulfide-cos-hydrogen-sulfide-h2s-donation-from-%C3%AE-ketothiocarbamate-donor-motifs
#8
Yu Zhao, Andrea Steiger, Michael Dwight Pluth
Hydrogen sulfide (H2S) is a biologically-active molecule that exhibits protective effects in a variety of physiological and pathological processes. Although a number of H2S-related biological effects have been discovered by using H2S donors, knowing how much H2S has been released from donors under different conditions remains a significant challenge. Aligned with this need, we report here a series of γ-ketothiocarbamate (γ-KetoTCM) compounds that provide the first examples of colorimetric H2S donors and enable direct quantification of H2S release...
August 13, 2018: Angewandte Chemie
https://www.readbyqxmd.com/read/30101887/a-robust-method-for-the-determination-of-cr-vi-and-cr-iii-in-industrial-wastewaters-by-liquid-chromatography-inductively-coupled-plasma-mass-spectrometry-combined-with-a-chelating-pretreatment-with-2-6-pyridinedicarboxylic-acid
#9
Kaori Shigeta, Ai Fujita, Tetsuya Nakazato, Hiroaki Tao
We have developed a method for the determination of Cr(VI) and Cr(III) in industrial wastewater by liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS) combined with a chelating pretreatment with 2,6-pyridinedicarboxylic acid (PDCA). The PDCA unified the chemical forms of the Cr(III) species in water samples by the formation of a stable Cr(III)-PDCA complex, which was then separated by a LC column. The chromatographic mobile phase at neutral pH and the column of a mixed-bed of anion and cation exchangers successfully separated not only the chromium species without any redox conversion, but also chloride, which interfered with ICP-MS detection...
2018: Analytical Sciences: the International Journal of the Japan Society for Analytical Chemistry
https://www.readbyqxmd.com/read/30101885/a-rapid-enrichment-technique-for-the-ultratrace-determination-of-nickel-in-water-samples-using-a-nanofiber-composite-membrane-filter
#10
Hitoshi Mizuguchi, Ryota Ishida, Yasushi Kouno, Tadahiko Tachibana, Tomomi Honda, Tatsuro Kijima, Yuhei Yamamoto, Toshio Takayanagi
A new method for the rapid enrichment and highly sensitive determination of nickel ion has been developed by using a nanofiber-composite membrane filter, which was fabricated by stacking a nanofibrous material made of nylon 6 over a water-permeable membrane filter. The noncharged nickel-α-furil dioxime complex was adsorbed on a nanofibrous layer of the membrane filter under significantly higher flow rates than those used for conventional solid-phase extraction techniques. Highly sensitive determinations with detection limits at sub-parts per billion levels were achieved by enrichment from 50 mL of the complex solution, and the enrichment was completed within 3 min...
2018: Analytical Sciences: the International Journal of the Japan Society for Analytical Chemistry
https://www.readbyqxmd.com/read/30101245/co-assemblies-of-polydiacetylenes-and-metal-ions-for-solvent-sensing
#11
Si Wu, Libin Pan, Youju Huang, Ni Yang, Qijin Zhang
We demonstrate an easy and low-cost approach for the colorimetric differentiation of organic solvents using co-assemblies of polydiacetylenes (PDAs) and metal ions. The co-assemblies were prepared by the self-assembly of amphiphilic 10,12-tricosa diynoic acid with different metal ions (Zn2+, Cu2+, Ni2+, Ca2+) and subsequent photopolymerization. Different metal ions underwent different interactions with the carboxyl groups on the side chains of poly(10,12-tricosa diynoic acid), which influenced the stimuli-responsiveness of the PDA/metal ion co-assemblies...
August 13, 2018: Soft Matter
https://www.readbyqxmd.com/read/30100454/black-goji-as-a-potential-source-of-natural-color-in-a-wide-ph-range
#12
Peipei Tang, M Monica Giusti
Lycium ruthenicum Murr. is a traditional Chinese herb widely distributed in Tibet. The fruit, known as black goji, is popular in traditional Chinese medicine. The objective of this study was to investigate its anthocyanin profile (by HPLC coupled to PDA and MS detectors) and the colorimetric and spectrophotometric properties. Black goji extracts contained abundant petunidin derivatives, with cis and trans isomers of petunidin-3-p-coumaroyl-rutinoside-5-glucoside. The colorimetric and spectrophotometric traits of black goji anthocyanins were significantly impacted by solid-phase-extraction, pH, and acylation...
December 15, 2018: Food Chemistry
https://www.readbyqxmd.com/read/30099608/determination-of-bacterial-dna-based-on-catalytic-oxidation-of-cysteine-by-g-quadruplex-dnazyme-generated-from-asymmetric-pcr-application-to-the-colorimetric-detection-of-staphylococcus-aureus
#13
Jing Wang, Haigang Li, Tingting Li, Liansheng Ling
A one-step, one-tube colorimetric assay is described for the detection of bacterial double-stranded DNA (dsDNA). It utilizes a G-quadruplex DNAzyme produced by an asymmetric polymerase chain reaction (As-PCR) that catalyzes the oxidation of cysteine to form cystine. This results in the formation of oligonucleotide-modified gold nanoparticles via triplex formation, and eventually in a color change from red to blue that occurs within about 10 mins. This can be measured by ratiometric colorimetric (at 525 and 600 nm)...
August 11, 2018: Mikrochimica Acta
https://www.readbyqxmd.com/read/30099042/isolation-characterization-and-microwave-assisted-surface-modification-of-colocasia-esculenta-l-schott-mucilage-by-grafting-polylactide
#14
Abubakar Hamisu Mijinyawa, Geeta Durga, Anuradha Mishra
Mucilage (represented as CEM) is abundantly present in Colocasia esculenta (L.) Schott or taro and is a water-soluble neutral polysaccharide that can act as a binder, thickening agent, and matrix agent in the pharmaceutical fields of research. Presence of hydroxyl groups on its surface structure allows chemical modification. This study describes in details the synthesis and characterization of its graft copolymer with polylactide (CEM-g-PLA). The polymerization has performed using both the microwave irradiation and conventional methods...
August 9, 2018: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/30097937/curcumin-turmeric-as-an-environment-friendly-protein-gel-stain
#15
Biji T Kurien, Yaser Dorri, R Hal Scofield
Curcumin, the main curcuminoid in food spice turmeric, is insoluble in water at room temperature. We showed that curcumin can be solubilized in water with the application of heat (100 °C). Here we demonstrate that heat-solubilized curcumin can serve as a nontoxic and environment-friendly fluorescent/colorimetric reversible protein stain. Curcumin, the yellow pigment found in the rhizomes of the perennial herb Curcuma longa (turmeric), is insoluble in aqueous solvents. However, heat solubilization in water renders 1...
2018: Methods in Molecular Biology
https://www.readbyqxmd.com/read/30097923/protein-stains-and-applications
#16
Pazhani Sundaram
Staining of proteins separated on gels provides the basis for determination of the critical properties of these biopolymers, such as their molecular weight and/or charge. Detection of proteins on gels and blots require stains. These stains vary in sensitivity, ease of use, color, stability, versatility, and specificity. This review discusses different stains and applications with details on how to use the stains, and advantages and disadvantages of each stain. It also compiles some important points to be considered in imaging and evaluation...
2018: Methods in Molecular Biology
https://www.readbyqxmd.com/read/30097735/colorimetric-determination-of-sialic-acid-based-on-boronic-acid-mediated-aggregation-of-gold-nanoparticles
#17
Titilope John Jayeoye, Wilairat Cheewasedtham, Chatchai Putson, Thitima Rujiralai
The authors describe a rapid, sensitive and selective colorimetric assay for sialic acid (SA) based on the use of gold nanoparticles (AuNPs) modified with 3-aminophenylboronic acid (3-APBA) which acts as the recognition probe for SA. 3-APBA contains amino groups and boronic acid groups through which it can assemble on citrate stabilized AuNPs. It reacts with the cis-diol groups of SA by reversible formation of a cyclic boronate ester in slightly acidic buffer. Detection involves the sequential addition of AuNPs, phosphate buffer, 3-APBA and SA in a tube, vortex mixing, acquisition of photographic images or absorption spectra, and calculation of the result...
August 10, 2018: Mikrochimica Acta
https://www.readbyqxmd.com/read/30097627/dye-functionalized-sol-gel-matrix-on-carbon-nanotubes-for-refreshable-and-flexible-gas-sensors
#18
Jeongsu Kim, Haneul Yoo, Viet Anh Pham Ba, Narae Shin, Seunghun Hong
We report a colorimetric dye-functionalized sol-gel matrix on carbon nanotubes for use as a refreshable and flexible gas sensor with humidity calibration. Here, we fabricated gas sensors by functionalizing dye molecules on the top of carbon nanotube networks via a sol-gel method. Using hybrid gas sensors with different dye molecules, we could selectively detect various hazardous gases, such as NH3 , Cl2 and SO2 gases, via optical and electrical signals. The sensors exhibited rather large conductance changes of more than 50% following exposure to gas species with concentrations even under the permissible exposure limit...
August 10, 2018: Scientific Reports
https://www.readbyqxmd.com/read/30097117/aqueous-extracts-of-paeonia-suffruticosa-modulates-mitochondrial-proteostasis-by-reactive-oxygen-species-induced-endoplasmic-reticulum-stress-in-pancreatic-cancer-cells
#19
Yu-Huei Liu, Yui-Ping Weng, Hsin-Ying Tsai, Chao-Jung Chen, Der-Yen Lee, Ching-Liang Hsieh, Yang-Chang Wu, Jung-Yaw Lin
BACKGROUND: Pancreatic cancer (PC) remains the leading cause of cancer mortality, with limited therapeutic targets, and alterations in endoplasmic reticulum (ER)-related proteostasis may be a potential target for therapy. The root bark of Paeonia suffruticosa has been shown to inhibit cancer growth and metastasis, although its impact on PC is unknown. PURPOSE: To ascertain the anti-cancer effects of P. suffruticosa on oncogenic functions of PC and determine the detailed molecular mechanisms...
July 15, 2018: Phytomedicine: International Journal of Phytotherapy and Phytopharmacology
https://www.readbyqxmd.com/read/30096647/metabolite-profiling-of-green-extracts-of-corylus-avellana-leaves-by-1-h-nmr-spectroscopy-and-multivariate-statistical-analysis
#20
Antonietta Cerulli, Milena Masullo, Paola Montoro, Jan Hošek, Cosimo Pizza, Sonia Piacente
Corylus avellana L. (Betulaceae) leaves, consumed as infusion, are used in traditional medicine, for the treatment of hemorrhoids, varicose veins, phlebitis, and edema due to their astringent, vasoprotective, and antiedema properties. In previous works we reported from the leaves of Corylus avellana cv. "Tonda di Giffoni" diarylheptanoid derivatives, a class of plant secondary metabolites with a wide variety of bioactivities. With the aim to give an interesting and economically feasible opportunity to C...
July 26, 2018: Journal of Pharmaceutical and Biomedical Analysis
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