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Find video protocols related to scientific articles indexed in Pubmed.
Supramolecular assembly of macroscopic building blocks through self-propelled locomotion by dissipating chemical energy.
Small
PUBLISHED: 04-03-2014
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Chemical energy supplied by the catalytic decomposition of H2 O2 is introduced into macroscopic building blocks, which self-propel, interact with each other, and finally assemble into ordered and advanced structures. The geometry is highly dependent on the way that the catalyst is loaded. The integration of catalyst and building block provides assembling component as well as its energy of motion.
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A novel alternate feeding mode for semi-continuous anaerobic co-digestion of food waste with chicken manure.
Bioresour. Technol.
PUBLISHED: 02-21-2014
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A novel alternate feeding mode was introduced to study the possibilities of improving methane yield from anaerobic co-digestion of food waste (FW) with chicken manure (CM). Two kinds of feeding sequence (a day FW and next day CM (FM/CM), two days FM and the third day CM (FW/FM/CM)) were investigated in semi-continuous anaerobic digestion and lasted 225 days, and the mono-digestions of FW and CM were used as control group, respectively. The feeding sequence of FW/CM and mono-digestion of CM were observed to fail to produce gas at hydraulic retention time (HRT) of 70 days due to the ammonia inhibition, however, the mode of FW/FM/CM was proved to successfully run at HRT of 35 days with a higher OLR of 2.50 kg L(-1)d(-1) and obtain a higher methane production rate of 507.58 ml g(-1) VS and volumetric biogas production rate of 2.1 L L(-1)d(-1).
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Synthesis of Au nanoparticles decorated graphene oxide nanosheets: noncovalent functionalization by TWEEN 20 in situ reduction of aqueous chloroaurate ions for hydrazine detection and catalytic reduction of 4-nitrophenol.
J. Hazard. Mater.
PUBLISHED: 08-15-2011
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In this paper, we develop a cost-effective and simple route for the synthesis of Au nanoparticles (AuNPs) decorated graphene oxide (GO) nanosheets using polyoxyethylene sorbitol anhydride monolaurate (TWEEN 20) as a stabilizing agent for GO as well as a reducing and immobilizing agent for AuNPs. The AuNPs assemble on the surface of TWEEN-functionalized GO by the in situ reduction of HAuCl(4) aqueous solution. The morphologies of these composites were characterized by atomic force microscopy (AFM) and transmission electron microscopy (TEM). It is found that the resultant AuNPs decorated GO nanosheets (AuNPs/TWEEN/GO) exhibit remarkable catalytic performance for hydrazine oxidation. This hydrazine sensor has a fast amperometric response time of less than 3s. The linear range is estimated to be from 5 ?M to 3 mM (r=0.999), and the detection limit is estimated to be 78 nM at a signal-to-noise ratio of 3. The AuNPs/TWEEN/GO composites also exhibit good catalytic activity toward 4-nitrophenol (4-NP) reduction and the GO supports also enhance the catalytic activity via a synergistic effect.
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A new preparation of Au nanoplates and their application for glucose sensing.
Biosens Bioelectron
PUBLISHED: 05-27-2011
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The present communication demonstrates a relatively green preparative route toward Au nanoplates in aqueous solution at room temperature with the use of tannic acid (TA), which is an environmentally friendly, soluble polyphenol, as a reducing agent. Such Au nanoplates exhibit notable catalytic performance toward the oxidation and reduction of H(2)O(2). A glucose biosensor was further fabricated by immobilizing glucose oxidase (GOD) into chitosan-Au nanoplate composites film on the surface of glassy carbon electrode (GCE). This sensor exhibits good response to glucose, and the linear response range is estimated to be from 2 to 20 mM (R=0.999) at 0.65 V and from 2 to 10 mM (R=0.993) at -0.2 V, respectively. The sensitivity of the sensor determined from the slopes is 49.5 ?A mM(-1)cm(-2) at 0.65 V.
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A novel single fluorophore-labeled double-stranded oligonucleotide probe for fluorescence-enhanced nucleic acid detection based on the inherent quenching ability of deoxyguanosine bases and competitive strand-displacement reaction.
J Fluoresc
PUBLISHED: 04-13-2011
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We develop a novel single fluorophore-labeled double-stranded oligonucleotide (OND) probe for rapid, nanostructure-free, fluorescence-enhanced nucleic acid detection for the first time. We further demonstrate such probe is able to well discriminate single-base mutation in nucleic acid. The design takes advantage of an inherent quenching ability of guanine bases. The short strand of the probe is designed with an end-labeled fluorophore that is placed adjacent to two guanines as the quencher located on the long opposite strand, resulting in great quenching of dye fluorescence. In the presence of a target complementary to the long strand of the probe, a competitive strand-displacement reaction occurs and the long strand forms a more stable duplex with the target, resulting in the two strands of the probe being separated from each other. As a consequence of this displacement, the fluorophore and the quencher are no longer in close proximity and dye fluorescence increases, signaling the presence of target.
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Poly(2,3-diaminonaphthalene) microspheres as a novel quencher for fluorescence-enhanced nucleic acid detection.
Analyst
PUBLISHED: 03-31-2011
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In this Communication, we report on the first preparation of conjugation polymer poly(2,3-diaminonaphthalene) (PDAN) microspheres via chemical oxidation polymerization of 2,3-diaminonaphthalene (DAN) monomers by ammonium persulfate (APS) at room temperature. We further demonstrate the use of PDAN microspheres as a novel quencher for fluorescence-enhanced nucleic acid detection.
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Fluorescence-enhanced potassium ions detection based on inherent quenching ability of deoxyguanosines and K(+)-induced conformational transition of G-rich ssDNA from duplex to G-quadruplex structures.
J Fluoresc
PUBLISHED: 03-23-2011
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Herein, we develop a novel single fluorophore-labeled double-stranded oligonucleotide (OND) probe for rapid fluorescence-enhanced K(+) detection, based on an inherent quenching ability of guanine bases and G-rich OND conformation transition from duplex to G-quadruplex. This probe presents high sensitivity and good selectivity for the detection of K(+), and the assay process is simple and fast.
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Separation of ionic liquid [Mmim][DMP] and glucose from enzymatic hydrolysis mixture of cellulose using alumina column chromatography.
Appl. Microbiol. Biotechnol.
PUBLISHED: 03-14-2011
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Pretreatment of cellulose with ionic liquids (ILs) can improve the efficiency of the hydrolysis by increasing the surface area of the substrates accessible to solvents and cellulases. However, the IL methods are facing challenges to separate the hydrolyzed sugar products as well as the renewable ILs from the complex hydrolysis mixtures. In this study, an alumina column chromatography (ACC) method was developed for the separation of hydrophilic IL N-methyl-N-methylimidazolium dimethyl phosphate ([Mmim][DMP]) and glucose, which was the main ingredient of the monosaccharide hydrolyzate. The processing parameters involved in ACC separation were investigated in detail. Our results showed that the recovery yields of [Mmim][DMP] and glucose can reach up to 93.38% and 90.14%, respectively, under the optimized parameters: the sampling ratio of 1:20 between the applied sample volume and the bed volume of the column; a gradient elution using methanol (100%, 150 ml) and then water (170 ml) as eluents with 1 ml/min flow rate. The recovered [Mmim][DMP] showed qualified property and was effective in a new hydrolysis reaction. In addition, scale-up ACC separations were successfully done with satisfied separation performance. The results indicated that the ACC is one of the available methods for the separation of ILs and monosaccharides from the hydrolysis mixtures.
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A novel fluorescent aptasensor for thrombin detection: using poly(m-phenylenediamine) rods as an effective sensing platform.
Chem. Commun. (Camb.)
PUBLISHED: 02-24-2011
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In this communication, we develop a novel fluorescent aptasensor for thrombin detection with the use of poly(m-phenylenediamine) (PMPD) rods as an effective sensing platform. This aptasensor exhibits extraordinarily high sensitivity with a detection limit as low as 100 pM and excellent selectivity.
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Coordination polymer nanobelts as an effective sensing platform for fluorescence-enhanced nucleic acid detection.
Macromol Rapid Commun
PUBLISHED: 02-23-2011
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In this communication, the application of coordination polymer nanobelts (CPNs) assembled from H(2)PtCl(6) and 3,3,5,5-tetramethylbenzidine (TMB) are explored as an effective fluorescent sensing platform for nucleic acid detection for the first time. The suggested method has a high selectivity down to single-base mismatch. DNA detection is accomplished by the following two steps: (1) CPN binds fluorecent dye-labeled single-stranded DNA (ssDNA) probe via both electrostatic attraction and ?-? stacking interactions between unpaired DNA bases and CPN. As a result, the fluorescent dye is brought into close proximity to CPN and substantial fluorescence quenching occurs due to photoinduced electron transfer from the nitrogen atom in CPN to the excited fluorophore. (2) The hybridization of adsorbed ssDNA probe with its target generates a double stranded DNA (dsDNA). The duplex cannot be adsorbed by CPN due to its rigid conformation and the absence of unpaired DNA bases, leading to an obvious fluorescence enhancement.
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Analysis of urinary metabolic profile in aging rats undergoing caloric restriction.
Aging Clin Exp Res
PUBLISHED: 02-21-2011
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While caloric restriction (CR) is associated with a prolonged lifespan in multiple species by regulating metabolism, a comprehensive profile of metabolism under CR conditions remains largely unclear. Therefore, in this study we aimed to characterize the metabolomic profiling associated with CR using a rat model.
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Poly(m-phenylenediamine) nanospheres and nanorods: selective synthesis and their application for multiplex nucleic acid detection.
PLoS ONE
PUBLISHED: 02-14-2011
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In this paper, we demonstrate for the first time that poly(m-phenylenediamine) (PMPD) nanospheres and nanorods can be selectively synthesized via chemical oxidation polymerization of m-phenylenediamine (MPD) monomers using ammonium persulfate (APS) as an oxidant at room temperature. It suggests that the pH value plays a critical role in controlling the the morphology of the nanostructures and fast polymerization rate favors the anisotropic growth of PMPD under homogeneous nucleation condition. We further demonstrate that such PMPD nanostructures can be used as an effective fluorescent sensing platform for multiplex nucleic acid detection. A detection limit as low as 50 pM and a high selectivity down to single-base mismatch could be achieved. The fluorescence quenching is attributed to photoinduced electron transfer from nitrogen atom in PMPD to excited fluorophore. Most importantly, the successful use of this sensing platform in human blood serum system is also demonstrated.
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Ag@poly(m-phenylenediamine) core-shell nanoparticles for highly selective, multiplex nucleic acid detection.
Langmuir
PUBLISHED: 02-08-2011
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In this letter, we report on the one-step synthesis of Ag@poly(m-phenylenediamine) core-shell nanoparticles (APCSNPs), carried out by direct mixing of aqueous silver nitrate and m-phenylenediamine solutions at room temperature. We further demonstrate the use of APCSNP as a novel fluorescent sensing platform for nucleic acid detection. In this regard, the detection of DNA is accomplished in two steps. First, APCSNP absorbs and quenches the fluorescence of dye-labeled single-stranded DNA (ssDNA) as a probe. Second, hybridizing of the probe with its target produces a double-stranded DNA (dsDNA) that detaches from APCSNP, resulting in the recovery of dye fluorescence. It suggests that this sensing system has a high selectivity down to single-base mismatch, and the results exhibit good reproducibility. Furthermore, we also demonstrate its application for the multiplex detection of nucleic acid sequences.
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Mesoporous carbon microparticles as a novel fluorescent sensing platform for thrombin detection.
Biosens Bioelectron
PUBLISHED: 01-19-2011
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The present paper presents the novel use of MC microparticles (MCMPs) as a novel fluorescent sensing platform for thrombin detection. The MCMPs were prepared by a nanocasting method using mesoporous silica (MS) NPs as a hard template. The general concept used in this approach lies in the facts that the non-covalent adsorption of the dye-labeled TA on MCMP driven by ?-? stacking of DNA bases on MCMP leads to substantial quenching of dye fluorescence due to their very close proximity. However, the presence of target TB results in the change of TA conformation to quadruplex due to the quadruplex-TB complex formation. Because the binding between the complex and MCMP is not strong enough to guarantee the close proximity of dyes to MCMP surface, fluorescence quenching is suppressed. This sensing system has a low detection limit down to 0.25nM and exhibits excellent selectivity. We also demonstrate its application in human blood serum system.
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Nano-C(60) : a novel, effective, fluorescent sensing platform for biomolecular detection.
Small
PUBLISHED: 01-12-2011
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Water-soluble nano-C(60) can serve as a novel, effective, fluorescent sensing platform for biomolecular detection with high sensitivity and selectivity. In this paper, fluorescent detection of DNA and thrombin via nano-C(60) is demonstrated for the first time. The principle of the assay lies in the fact that the adsorption of the fluorescently labeled single-stranded DNA (ssDNA) probe by nano-C(60) leads to substantial fluorescence quenching. In the presence of a target, the biomolecular mutual interaction suppresses this quenching, signaling the existence of the target. This sensing system rivals graphene oxide but is superior to other carbon-structure-based systems. The present method can also achieve multiplex DNA detection and withstand the interference from human blood serum.
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Poly(o-phenylenediamine) colloid-quenched fluorescent oligonucleotide as a probe for fluorescence-enhanced nucleic acid detection.
Langmuir
PUBLISHED: 12-27-2010
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In this Letter, we demonstrate that chemical oxidation polymerization of o-phenylenediamine (OPD) by potassium bichromate at room temperature results in the formation of submicrometer-scale poly(o-phenylenediamine) (POPD) colloids. Such colloids can absorb and quench dye-labeled single-stranded DNA (ssDNA) very effectively. In the presence of a target, a hybridization event occurs, which produces a double-stranded DNA (dsDNA) that detaches from the POPD surface, leading to recovery of dye fluorescence. With the use of an oligonucleotide (OND) sequence associated with human immunodeficiency virus (HIV) as a model system, we demonstrate the proof of concept that POPD colloid-quenched fluorescent OND can be used as a probe for fluorescence-enhanced nucleic acid detection with selectivity down to single-base mismatch.
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Conjugation polymer nanobelts: a novel fluorescent sensing platform for nucleic acid detection.
Nucleic Acids Res.
PUBLISHED: 12-22-2010
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In this article, we report on the facile and rapid synthesis of conjugation polymer poly(p-phenylenediamine) nanobelts (PNs) via room temperature chemical oxidation polymerization of p-phenylenediamine monomers by ammonium persulfate in aqueous medium. We further demonstrate the proof-of-concept that PNs can be used as an effective fluorescent sensing platform for nucleic acid detection for the first time. The general concept used in this approach lies in the facts that the adsorption of the fluorescently labeled single-stranded DNA probe by PN leads to substantial fluorescence quenching, followed by specific hybridization with the complementary region of the target DNA sequence. This results in desorption of the hybridized complex from PN surface and subsequent recovery of fluorescence. We also show that the sensing platform described herein can be used for multiplexing detection of nucleic acid sequences.
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A novel single-labeled fluorescent oligonucleotide probe for silver(I) ion detection based on the inherent quenching ability of deoxyguanosines.
Analyst
PUBLISHED: 12-15-2010
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A novel single-labeled fluorescent oligonucleotide (OND) probe for the detection of nanomolar silver(I) ion in aqueous solution is developed based on the inherent quenching ability of deoxyguanosines. The formation of a hairpin structure of the OND-Ag(+) complex brings deoxyguanosines close to a dye, leading to a decreased fluorescence intensity of the dye owning to photoinduced electron transfer from the dye to deoxyguanosines.
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Influence of polyols on the formation of iron oxide nanoparticles in solvothermal system.
J Nanosci Nanotechnol
PUBLISHED: 12-03-2010
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We reported a simple solvothermal route in phase-controllable synthesis of iron oxide nanoparticles by using polyols as solvent. Magnetite and hematite are selectively synthesized while Fe(NO3)3.9H2O is used as single iron source and without any additives. While ethylene glycol, 1,2propanediol, 1,3-butanediol, or glycerol is used as solvents, magnetite nanoparticles are obtained, and the average particle sizes vary from 10 to 40 nm. While 1,4-butanediol or 1,5-pentanediol is used as solvents, hematite nanoparticles are obtained. Our results suggest that the polyols with neighboring hydroxyl groups is favorable for the formation of magnetite nanoparticles.
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Nucleic acid detection using carbon nanoparticles as a fluorescent sensing platform.
Chem. Commun. (Camb.)
PUBLISHED: 11-15-2010
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In this communication, we demonstrate for the first time the proof of concept that carbon nanoparticles (CNPs) can be used as an effective fluorescent sensing platform for nucleic acid detection with selectivity down to single-base mismatch. The dye-labeled single-stranded DNA (ssDNA) probe is adsorbed onto the surface of the CNP via ?-? interaction, quenching the dye. In the target assay, a double-stranded DNA (dsDNA) hybrid forms, recovering dye fluorescence.
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A novel single-labeled fluorescent oligonucleotide probe for mercury(II) ion detection: using the inherent quenching of deoxyguanosines.
J Fluoresc
PUBLISHED: 09-23-2010
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A novel single-labeled fluorescent oligonucleotide (OND) probe for the detection of nanomolar mercury(II) ion in aqueous solution is developed based on the inherent quenching of deoxyguanosines. The formation of hairpin structure of OND-Hg(2+) complex brings deoxyguanosines close to dye, resulting in decreased dye fluorescence due to photoinduced electron transfer from dye to deoxyguanosines.
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Increasing fatty acid production in E. coli by simulating the lipid accumulation of oleaginous microorganisms.
J. Ind. Microbiol. Biotechnol.
PUBLISHED: 06-20-2010
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Unlike many oleaginous microorganisms, E. coli only maintains a small amount of natural lipids in cells, impeding its utility to overproduce fatty acids. In this study, acetyl-CoA carboxylase (ACC) from Acinetobacter calcoaceticus was expressed in E. coli to redirect the carbon flux to the generation of malonyl-CoA, which resulted in a threefold increase in intracellular lipids. Moreover, providing a high level of NADPH by overexpressing malic enzyme and adding malate to the culture medium resulted in a fourfold increase in intracellular lipids (about 197.74 mg/g). Co-expression of ACC and malic enzyme resulted in 284.56 mg/g intracellular lipids, a 5.6-fold increase compared to the wild-type strain. This study provides some attractive strategies for increasing lipid production in E. coli by simulating the lipid accumulation of oleaginous microorganisms, which could aid the development of a prokaryotic fatty acid producer.
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B5, a novel pyrrole-substituted indolinone, exerts potent antitumor efficacy through G2/M cell cycle arrest.
Invest New Drugs
PUBLISHED: 01-13-2009
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(E)-Ethyl 3,5-dimethyl-4-[(indolin-2-one-3-ylidene)methyl]-1H-pyrrole-2-carboxylate (B5) was one of the novel pyrrole-substituted indolinones synthesized in our research with the initial aim of developing selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKIs). However, B5 exhibited weak inhibitory potency against a variety of protein tyrosine kinases including EGFR, but potent kinase inhibition against several members of the cyclin-dependent kinase (CDK) family. The results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay demonstrated that B5 had approximately 500 times more potent antitumor activity than PD153035, a known standard EGFR-TKI, in a panel of ten epithelial cancer cell lines. B5 did not inhibit the phosphorylation of EGFR induced by EGF in vitro. DNA flow cytometric analysis revealed that B5 induced cell cycle arrest at G2/M phase and western blot analysis indicated that both CDK1 (Cdc2) and cyclin B1 proteins were decreased after B5 treatment. Our findings suggested the potential therapeutic applications of B5 in numerous cancers and a promising new template for further development of antitumor agents.
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Biomolecule-assisted, environmentally friendly, one-pot synthesis of CuS/reduced graphene oxide nanocomposites with enhanced photocatalytic performance.
Langmuir
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In this work, we develop a novel environmentally friendly strategy toward one-pot synthesis of CuS nanoparticle-decorated reduced graphene oxide (CuS/rGO) nanocomposites with the use of L-cysteine, an amino acid, as a reducing agent, sulfur donor, and linker to anchor CuS nanoparticles onto the surface of rGO sheets. Upon visible light illumination (? > 400 nm), the CuS/rGO nanocomposites show pronounced enhanced photocurrent response and improved photocatalytic activity in the degradation of methylene blue (MB) compared to pure CuS. This could be attributed to the efficient charge transport of rGO sheets and hence reduced recombination rate of excited carriers.
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Economical, green synthesis of fluorescent carbon nanoparticles and their use as probes for sensitive and selective detection of mercury(II) ions.
Anal. Chem.
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The present article reports on a simple, economical, and green preparative strategy toward water-soluble, fluorescent carbon nanoparticles (CPs) with a quantum yield of approximately 6.9% by hydrothermal process using low cost wastes of pomelo peel as a carbon source for the first time. We further explore the use of such CPs as probes for a fluorescent Hg(2+) detection application, which is based on Hg(2+)-induced fluorescence quenching of CPs. This sensing system exhibits excellent sensitivity and selectivity toward Hg(2+), and a detection limit as low as 0.23 nM is achieved. The practical use of this system for Hg(2+) determination in lake water samples is also demonstrated successfully.
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Metabonomic investigation on the protective effects of rosiglitazone and caloric restriction for renal senescence in a rat model.
Aging Clin Exp Res
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A liquid chromatography coupled with mass spectrometry based metabonomics approach was applied to investigate the protective effects of rosiglitazone (RGTZ) and caloric restriction (CR) for renal senescence in a rat model.
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Environmentally friendly, one-pot synthesis of Ag nanoparticle-decorated reduced graphene oxide composites and their application to photocurrent generation.
Inorg Chem
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In this paper, we develop an environmentally friendly, one-pot strategy toward rapid preparation of Ag nanoparticle-decorated reducd graphene oxide (AgNPs/rGO) composites by heating the mixture of GO and AgNO(3) aqueous solution in the presence of sodium hydroxide at 80 °C under stirring. The reaction was accomplished within a short period of 10 min without extra reducing agent. As-synthesized AgNPs/rGO composites have been successfully applied in photocurrent generation in the visible spectral region.
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Hydrothermal treatment of grass: a low-cost, green route to nitrogen-doped, carbon-rich, photoluminescent polymer nanodots as an effective fluorescent sensing platform for label-free detection of Cu(II) ions.
Adv. Mater. Weinheim
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Increasing reaction temperature produces photoluminescent polymer nanodots (PPNDs) with decreased particle size and increased quantum yield. Such PPNDs are used as an effective fluorescent sensing platform for label-free sensitive and selective detection of Cu(II) ions with a detection limit as low as 1 nM. This method is successfully applied to determine Cu(2+) in real water samples.
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Novel application of CoFe layered double hydroxide nanoplates for colorimetric detection of H(2)O(2) and glucose.
Analyst
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The present communication demonstrates the proof of concept of using CoFe layered double hydroxide (CoFe-LDHs) nanoplates as an effective peroxidase mimetic to catalyze the oxidation of peroxidase substrate 3,3,5,5-tetramethylbenzidine in the presence of H(2)O(2) to produce a blue solution. We further demonstrate successfully CoFe-LDHs nanoplate-based colorimetric assay to detect H(2)O(2) and glucose.
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Novel use of poly(3,4-ethylenedioxythiophene) nanoparticles for fluorescent nucleic acid detection.
ACS Comb Sci
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In this paper, we demonstrate the novel use of poly(3,4-ethylene dioxythiophene) (PEDOT) nanoparticle as a very effective fluorescent sensing platform for the detection of nucleic acid sequences. The principle of the assay lies in the fact that the adsorption of the fluorescently labeled single-stranded DNA (ssDNA) probe by PEDOT nanoparticle leads to substantial fluorescence quenching, followed by specific hybridization with the complementary region of the target DNA sequence. This results in desorption of the hybridized complex from PEDOT nanoparticle surface and subsequent recovery of fluorescence. A detection limit as low as 30 pM could be achieved in this sensing system. We also demonstrate its application for multiplexed detection of nucleic acid sequences. Furthermore, this sensing system can realize the detection of single-base mismatch even in multiplexed format. It is of importance to note that the successful use of this sensing platform in human blood serum system is also demonstrated.
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Rectangular coordination polymer nanoplates: large-scale, rapid synthesis and their application as a fluorescent sensing platform for DNA detection.
PLoS ONE
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In this paper, we report on the large-scale, rapid synthesis of uniform rectangular coordination polymer nanoplates (RCPNs) assembled from Cu(II) and 4,4-bipyridine for the first time. We further demonstrate that such RCPNs can be used as a very effective fluorescent sensing platform for multiple DNA detection with a detection limit as low as 30 pM and a high selectivity down to single-base mismatch. The DNA detection is accomplished by the following two steps: (1) RCPN binds dye-labeled single-stranded DNA (ssDNA) probe, which brings dye and RCPN into close proximity, leading to fluorescence quenching; (2) Specific hybridization of the probe with its target generates a double-stranded DNA (dsDNA) which detaches from RCPN, leading to fluorescence recovery. It suggests that this sensing system can well discriminate complementary and mismatched DNA sequences. The exact mechanism of fluorescence quenching involved is elucidated experimentally and its use in a human blood serum system is also demonstrated successfully.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.