Aggregation-Induced Emission of Au/Ag Alloy Nanoclusters for Fluorescence Detection of Inorganic Pyrophosphate and Pyrophosphatase Activity

The development of sensitive and accurate detection of inorganic pyrophosphate (PPi) and pyrophosphatase activity (PPase) is important as they play vital roles in biological systems. However, it is still not satisfactory for most of the analytical methods for PPi and PPase because of their Cu2+-dependence and poor accuracy. Although the metal ion triggered aggregation-induced emission (AIE) of metal nanoclusters (NCs) offers a new approach to design a Cu2+-free strategy for the accurate determination of PPi and PPase recently, current methods are all focused on utilizing pure metal NCs. Alloy NCs incorporating the advantages of diverse metal usually can achieve improved behaviors in the application, such as enhanced sensitivity and stability. In this work, glutathione stabilized alloy Au/Ag NCs were synthesized via a simple method and used for the fluorescence detection of PPi and PPase based on a Zn2+-regulated AIE strategy. The controlled release of Zn2+ by PPi and PPase could regulate the AIE of Au/Ag NCs and be employed to response PPi concentration and PPase activity. This method processes simple procedure, high sensitivity and stability, and low toxicity. In addition, we also studied the AIE behaviors of this Au/Ag NCs and offer some fundamental understanding of the AIE properties of water-soluble alloy NCs. This study not only provides a straightforward and new approach for PPi and PPase determination but a basis for further study on the AIE properties of alloy NCs and their application.

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The pyrophosphatase activity of pig kidney alkaline phosphatase and its inhibition by magnesium ions and excess of pyrophosphate

Biochemical Journal ◽

10.1042/bj1100671 ◽

1968 ◽

Vol 110 (4) ◽

pp. 671-675 ◽

Cited By ~ 19

Author(s):

P. J. Butterworth

Keyword(s):

Metal Ion ◽

Total Concentration ◽

Alkaline Phosphatases ◽

Inorganic Pyrophosphate ◽

Pig Kidney ◽

A Value ◽

Pyrophosphatase Activity ◽

Concentration Curves ◽

Kidney Alkaline Phosphatase ◽

Complex Ion

1. Pig kidney enzyme resembles other non-specific alkaline phosphatases in its ability to hydrolyse inorganic pyrophosphate (PPi). 2. Studies of enzyme velocity as a function of PPi concentration show that Michaelis–Menten kinetics are obeyed when a constant PPi/Mg2+ concentration ratio is maintained, but velocity–substrate concentration curves are sigmoid when the concentration of PPi is increased but that of Mg2+ is kept constant. The enzyme is inhibited when the total PPi concentration is greater than the total concentration of Mg2+. Pyrophosphatase activity is activated by Mg2+, but if the concentration of the metal ion is increased to a value in excess of the total PPi concentration Mg2+ is then strongly inhibitory. 4. It appears that the enzyme is most active towards the complex ion MgPPi2−. The enzyme probably hydrolyses PPi4− also, but this is a poorer substrate and its competition with MgPPi2− leads to inhibition. At high Mg2+ concentrations Mg2PPi is formed. This complex appears to be a potent inhibitor. 5. Sigmoid plots of v against s and of v against i result from interactions occurring between Mg2+ and PPi4− leading to MgPPi2− and Mg2PPi, and are not indicative of allosteric behaviour.

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PROBING PROTEINS AND DIFFERENTIATING THEIR NATIVE AND DENATURED STATES WITH AGGREGATION-INDUCED EMISSION FLUOROGEN

Journal of Molecular and Engineering Materials ◽

10.1142/s2251237313400054 ◽

2013 ◽

Vol 01 (03) ◽

pp. 1340005 ◽

Cited By ~ 3

Author(s):

CHRIS WAI TUNG LEUNG ◽

YUNING HONG ◽

BEN ZHONG TANG

Keyword(s):

Cytochrome C ◽

Protein Detection ◽

Water Soluble ◽

Simple Method ◽

Aggregation Induced Emission ◽

Fluorescence Change ◽

Protein Functions ◽

Group A ◽

Denatured States ◽

Comprehensive Study

The tertiary 3D structures of proteins determine their unique functions. Perturbation of their native state including denaturation may cause loss of the protein functions. In this work, water-soluble tetraphenylethylene (TPE) fluorophore, sodium 1,2-bis[4-(3-sulfonatopropoxyl)phenyl]-1,2-diphenylethene (BSPOTPE), with aggregation-induced emission (AIE) characteristics is utilized as a fluorescent probe for protein detection and for differentiating their folding modes. Owing to hydrophobic interaction between the proteins and BSPOTPE, it provides a fast and simple method to differentiate the native and denatured states of the proteins through monitoring fluorescence change in solution and PAGE gels. Six proteins are chosen as model proteins in the study. Among them, cytochrome c shows distinctive behavior to other proteins due to the presence of heme group. A comprehensive study of cytochrome c and human serum albumin is carried out in this work.

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Rational design of HA-AuNPs@AIEDs nanoassembly for activatable fluorescence detection of HAase and imaging in tumor cells.

Analytical Methods ◽

10.1039/d0ay02130j ◽

2021 ◽

Author(s):

Shenglan Wang ◽

Chong-Hua Zhang ◽

Peisheng Zhang ◽

Shu Chen ◽

Zhi-ling Song ◽

...

Keyword(s):

Optical Properties ◽

Tumor Cells ◽

Fluorescence Detection ◽

Rational Design ◽

High Brightness ◽

Aggregation Induced Emission ◽

Fluorescence Bioimaging ◽

In Virtue Of

Aggregation induced emission (AIE) dots have gained broad attention in fluorescence bioimaging and biosensor in virtue of their distinctive optical properties of splendid biocompatibility, high brightness and good photostability. However,...

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Identification and functional analysis of cadmium-binding protein in the visceral mass of Crassostrea gigas

Scientific Reports ◽

10.1038/s41598-021-90882-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Zehua Zheng ◽

Kazuhiro Kawakami ◽

Dingkun Zhang ◽

Lumi Negishi ◽

Mohamed Abomosallam ◽

...

Keyword(s):

Crassostrea Gigas ◽

Metal Ion ◽

Defense Mechanisms ◽

Three Dimensional ◽

Tryptophan Fluorescence ◽

Water Soluble ◽

Titration Calorimetry ◽

Visceral Mass ◽

The Pacific ◽

Liquid Chromatography Tandem Mass

AbstractThe Pacific oyster, Crassostrea gigas, is a traditional food worldwide. The soft body of the oyster can easily accumulate heavy metals such as cadmium (Cd). To clarify the molecular mechanism of Cd accumulation in the viscera of C. gigas, we identified Cd-binding proteins. 5,10,15,20-Tetraphenyl-21H,23H-porphinetetrasulfonic acid, disulfuric acid, tetrahydrate, and Cd-binding competition experiments using immobilized metal ion affinity chromatography revealed the binding of water-soluble high molecular weight proteins to Cd, including C. gigas protein disulfide isomerase (cgPDI). Liquid chromatography–tandem mass spectrometry (LC–MS/MS) analyses revealed two CGHC motifs in cgPDI. The binding between Cd and rcgPDI was confirmed through a Cd-binding experiment using the TPPS method. Isothermal titration calorimetry (ITC) revealed the binding of two Cd ions to one molecule of rcgPDI. Circular dichroism (CD) spectrum and tryptophan fluorescence analyses demonstrated that the rcgPDI bound to Cd. The binding markedly changed the two-dimensional or three-dimensional structures. The activity of rcgPDI measured by a PDI Activity Assay Kit was more affected by the addition of Cd than by human PDI. Immunological analyses indicated that C. gigas contained cgPDI at a concentration of 1.0 nmol/g (viscera wet weight). The combination of ITC and quantification results revealed that Cd-binding to cgPDI accounted for 20% of the total bound Cd in the visceral mass. The findings provide new insights into the defense mechanisms of invertebrates against Cd.

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Capturing Protein Droplets: Label-free Visualization and Detection of Protein Liquid-Liquid Phase Separation with an Aggregation-Induced Emission Fluorogen

Chemical Communications ◽

10.1039/d1cc00947h ◽

2021 ◽

Author(s):

Yan-Mei Li ◽

Chu-Qiao Liang ◽

Lin Wang ◽

Yun-Yi Luo ◽

Qian-Qian Li

Keyword(s):

Phase Separation ◽

Liquid Phase ◽

Liquid Phase Separation ◽

New Method ◽

Label Free ◽

Simple Method ◽

Aggregation Induced Emission ◽

Liquid Liquid Phase Separation

We developed a new method for protein droplet visualization by means of a droplet probe (DroProbe) based on an aggregation-induced emission (AIE) fluorogen. A simple method for viscosity comparison of...

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Metal-ion-dependent oxidative DNA cleavage by transition metal complexes of a new water-soluble salen derivative

Journal of Inorganic Biochemistry ◽

10.1016/0162-0134(95)00228-6 ◽

1996 ◽

Vol 63 (4) ◽

pp. 265-272 ◽

Cited By ~ 37

Author(s):

Subhrangsu S. Mandal ◽

N. Vinay Kumar ◽

Umesh Varshney ◽

Santanu Bhattacharya

Keyword(s):

Transition Metal ◽

Metal Complexes ◽

Transition Metal Complexes ◽

Dna Cleavage ◽

Metal Ion ◽

Water Soluble ◽

Oxidative Dna Cleavage

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Novel Inorganic Hydrogels Based on The Polymerization of Cyanometalate Transition Metal Complexes With [PdCl4]2-: A New Approach To Ceramic And Alloy Precursors

MRS Proceedings ◽

10.1557/proc-346-89 ◽

1994 ◽

Vol 346 ◽

Author(s):

Andrew B. Bocarsly ◽

Gireesh Kumar ◽

Marija Heibel

Keyword(s):

Transition Metal ◽

Metal Ion ◽

Sol Gel ◽

Metallic Matrix ◽

Linear Polymers ◽

New Approach ◽

Square Planar ◽

Delafossite Structure ◽

Cyanide Ligand ◽

Sol Gel Transition

ABSTRACTThe reaction of a wide variety of cyanometalate complexes of the general form [M(CN)x]n- (where M= a transition metal ion) with square planar [PdCl4]2- in aqueous solution leads to the formation of linear polymers. Polymerization occurs via substitution of chloride ligands on the Pd(II) centers, by the nitrogen end of the cyanide ligand to generate extended bridging cyanide structures. Upon generation at room temperature polymer solutions of this type under go a sol-gel transition to generate robust hydrogels having water content in excess of 95%. In the case of the cyanocobaltate/tetrachloropalladate gel, pyrolysis at 900°C produces ferromagnetic Pd/Co metallic alloys having novel morphological character. Materials formed with a hydrogel having a 2:1 Pd to Co stoichiometry are found to be “sponge-like”. When placed in water, the metallic matrix swells becoming pliable and holding up to seven equivalents of water per metal site. The conductivity and magnetic properties of this material are maintained in the swollen state. Sintering of the Pd/Co hydrogel in air generates the layered oxide, PbCoO2 having a delafossite structure.

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A New Approach for Determining Joint Stiffness of Bolted Joints

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.670-671.1041 ◽

2014 ◽

Vol 670-671 ◽

pp. 1041-1044 ◽

Cited By ~ 1

Author(s):

Xi Wang Wang ◽

Xiao Yang Li ◽

Lin Lin Zhang ◽

Xiao Guang Wang

Keyword(s):

Accurate Determination ◽

Joint Stiffness ◽

Fatigue Loading ◽

Bolted Joints ◽

Analytical Models ◽

Bolted Connection ◽

New Approach ◽

Axisymmetric Model ◽

Force Equilibrium

Joint member stiffness in a bolted connection directly influence the safety of a design in regard to both static and fatigue loading as well as in the prevention of separation in the connection. Thus, the accurate determination of the stiffness is of extreme importance to predict the behavior of bolted assemblies. In this paper, An analytical 3D axisymmetric model of bolted joints is proposed to obtain the joint stiffness of Bolted Joints. Considering many different analytical models have been proposed to calculate the joint stiffness, the expression based force equilibrium can be a easy way to choose the best expression for the joint stiffness as a judgment criteria.

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