Surface charge density on spherical silica particles in aqueous alkali chloride solutions

Many bio-functions of cells can be regulated by their surface charge characteristics. Mapping surface charge density in a single cell’s surface is vital to advance the understanding of cell behaviors. This article demonstrates a method of cell surface charge mapping via electrostatic cell–nanoparticle (NP) interactions. Fluorescent nanoparticles (NPs) were used as the marker to investigate single cells’ surface charge distribution. The nanoparticles with opposite charges were electrostatically bonded to the cell surface; a stack of fluorescence distribution on a cell’s surface at a series of vertical distances was imaged and analyzed. By establishing a relationship between fluorescent light intensity and number of nanoparticles, cells’ surface charge distribution was quantified from the fluorescence distribution. Two types of cells, human umbilical vein endothelial cells (HUVECs) and HeLa cells, were tested. From the measured surface charge density of a group of single cells, the average zeta potentials of the two types of cells were obtained, which are in good agreement with the standard electrophoretic light scattering measurement. This method can be used for rapid surface charge mapping of single particles or cells, and can advance cell-surface-charge characterization applications in many biomedical fields.

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Design, synthesis, and catalytic performance of modified graphene oxide based on a cobalt complex as a heterogenous catalyst for the preparation of aminonaphthoquinone derivatives

RSC Advances ◽

10.1039/d1ra01790j ◽

2021 ◽

Vol 11 (28) ◽

pp. 17108-17115

Author(s):

Mahnaz Mirheidari ◽

Javad Safaei-Ghomi

Keyword(s):

Graphene Oxide ◽

Cobalt Complex ◽

Catalytic Performance ◽

Silica Particles ◽

Design Synthesis ◽

Spherical Silica ◽

Modified Graphene Oxide ◽

Spherical Silica Particles ◽

Heterogenous Catalyst ◽

Modified Graphene

GO@f-SiO2@Co is a heterogenous catalyst composed of spherical silica particles grafted on the surface of graphene oxide with ethylenediamine ligands and coordination with Co(ii). We assessed the activity of the catalyst for the synthesis of aminonaphthoquinones.

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Triboelectrification of nanocomposites using identical polymer matrixes with different concentrations of nanoparticle fillers

Journal of Materials Chemistry A ◽

10.1039/d0ta12441a ◽

2021 ◽

Author(s):

Linards Lapčinskis ◽

Artis Linarts ◽

Kaspars Mālnieks ◽

Hyunseung Kim ◽

Kristaps Rubenis ◽

...

Keyword(s):

Charge Density ◽

Surface Charge ◽

Surface Charge Density ◽

Polymer Layers

In this study, we investigate triboelectrification in polymer-based nanocomposites using identical polymer matrixes containing different concentrations of nanoparticles (NPs). The triboelectric surface charge density on polymer layers increased as the...

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Effect of Selected Anionic and Cationic Drugs Affecting the Central Nervous System on Electrical Properties of Phosphatidylcholine Liposomes: Experiment and Theory

International Journal of Molecular Sciences ◽

10.3390/ijms22052270 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2270

Author(s):

Joanna Kotyńska ◽

Monika Naumowicz

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Charge Density ◽

Surface Charge ◽

Surface Charge Density ◽

Barbituric Acid ◽

Membrane Surface ◽

Adsorption Equilibria ◽

Two Component ◽

The Central Nervous System

Interactions between phospholipid membranes and selected drugs affecting the central nervous system (CNS) were investigated. Small, unilamellar liposomes were used as biomimetic cell membrane models. Microelectrophoretic experiments on two-component liposomes were performed using the electrophoretic light scattering technique (ELS). The effect of both positively (perphenazine, PF) and negatively (barbituric acid, BA) charged drugs on zwitterionic L-α-phosphatidylcholine (PC) membranes were analyzed. Experimental membrane surface charge density (d) data were determined as a function of pH. Quantitative descriptions of the adsorption equilibria formed due to the binding of solution ions to analyzed two-component membranes are presented. Binding constants of the solution ions with perphenazine and barbituric acid-modified membranes were determined. The results of our research show that both charged drugs change surface charge density values of phosphatidylcholine membranes. It can be concluded that perphenazine and barbituric acid are located near the membrane surface, interacting electrostatically with phosphatidylcholine polar heads.

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Surface charging parameters of charged particles in symmetrical electrolyte solutions

Physical Chemistry Chemical Physics ◽

10.1039/d0cp02725a ◽

2020 ◽

Vol 22 (35) ◽

pp. 20123-20142

Author(s):

Hadi Saboorian-Jooybari ◽

Zhangxin Chen

Keyword(s):

Charge Density ◽

Surface Charge ◽

Electrolyte Solution ◽

Surface Charge Density ◽

Potential Surface ◽

Research Work ◽

Charged Particles ◽

Electrolyte Solutions ◽

Surface Charging ◽

Curvature Dependence

This research work is directed at development of accurate physics-based formulas for quantification of curvature-dependence of surface potential, surface charge density, and total surface charge for cylindrical and spherical charged particles immersed in a symmetrical electrolyte solution.

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A multi-dielectric-layered triboelectric nanogenerator as energized by corona discharge

Nanoscale ◽

10.1039/c7nr02249b ◽

2017 ◽

Vol 9 (27) ◽

pp. 9668-9675 ◽

Cited By ~ 28

Author(s):

Jia Jia Shao ◽

Wei Tang ◽

Tao Jiang ◽

Xiang Yu Chen ◽

Liang Xu ◽

...

Keyword(s):

Charge Density ◽

Surface Charge ◽

Corona Discharge ◽

Surface Charge Density ◽

High Surface ◽

Cycling Stability ◽

Triboelectric Nanogenerator ◽

Excellent Cycling Stability ◽

Vertical Contact ◽

High Surface Charge Density

A multi-dielectric-layered vertical contact-separation mode TENG through a corona discharge approach results in outstanding output performances, i.e., a high surface charge density of 283 μC m−2 and excellent cycling stability (92.6% retention after 200 000 cycles).

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