Faculty Opinions recommendation of Receptor activation alters inner surface potential during phagocytosis.

Environmental contextInterfacial properties of colloid and nanoparticles are directly related to the reactivity and surface densities of existing surface sites. Surface characterisation of particles provides only some kind of average surface properties. Analysis of well-defined monocrystal surfaces, which form the surface of the single particle, leads to a better understanding of surface reactions and mutual interactions of adjacent crystal planes on average surface properties. AbstractThe contact of small solid particles and macroscopic flat planes with aqueous electrolyte solutions results in the accumulation of ions at the interface and the formation of the electrical interfacial layer. Analysis of well-defined monocrystal surfaces, which are the building blocks of a single particle, leads to a better understanding of surface reactions and mutual interactions of adjacent crystal planes on average surface properties of particles. We analyse inner surface potential (obtained by single-crystal electrode) and zeta-potential data (obtained by streaming potential measurements) that were obtained on identical samples. Among the systems for which comparable surface and zetapotentials are available, measured inner surface potential data for sapphire (0001), haematite (0001) and rutile (110) show the expected behaviour based on the face-specific surface chemistry model, whereas the slopes for rutile (110) and quartz (0001) do not. Isoelectric points for sapphire (0001), haematite (0001) and rutile (100) are in conflict with the standard model that implies consistent behaviour of surface potential and diffuse layer potential. For the two former systems, previous results from the literature suggest that the charge of interfacial water can explain the discrepancy. The water layer could also play a role for quartz (0001), but in this case, the discrepancy would simply not be noticed, because both point of zero potential and isoelectric point are low. Along with data on silver halides, it can be concluded that six-ring water structures on solids may generate the electrokinetic behaviour that is typical of inert surfaces like Teflon.

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Effect of Water Adsorption on Cation-Surface Interaction Energy in the Na-Mordenite of 5.5 : 1 Si/Al Ratio

Journal of Chemistry ◽

10.1155/2016/2152180 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Sekou Diaby

Keyword(s):

Activation Energy ◽

Surface Properties ◽

Surface Potential ◽

Water Adsorption ◽

Adsorbed Water ◽

Material Surface ◽

Water Molecules ◽

Zeolite Surface ◽

Inner Surface ◽

Insight Into

The mobility of the Na+cations localized at the inner surface of the studied mordenite zeolite depends on the material surface properties. In this work, we show that the activation energy,ΔEhop, relating to the Na+cation hopping displacement is associated to the surface potential and therefore can be used to get a better insight into the zeolite surface properties. Indeed, when molecules as water are adsorbed at the surface, they modify the surface potential energy and hence influence the value ofΔEhop. If the adsorbed molecules are polar they directly interact with the cations which become more mobile. The more theΔEhopvalue is, the less the amount of adsorbed water molecules is. Alterations of theΔEhopvalue with respect to the amount of adsorbed water molecules are interpreted using the Dubinin model which is based on simple adsorption principle.

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Determination of the inner surface potential of the erythrocyte membrane

Bioelectrochemistry and Bioenergetics ◽

10.1016/s0302-4598(96)05181-1 ◽

1997 ◽

Vol 43 (1) ◽

pp. 97-103 ◽

Cited By ~ 13

Author(s):

Aleš Iglič ◽

Milan Brumen ◽

Saša Svetina

Keyword(s):

Erythrocyte Membrane ◽

Surface Potential ◽

Inner Surface

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Adsorption of Polyions on Flat TiO2 Surface

Minerals ◽

10.3390/min11111164 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1164

Author(s):

Tin Klačić ◽

Jozefina Katić ◽

Danijel Namjesnik ◽

Jasmina Jukić ◽

Davor Kovačević ◽

...

Keyword(s):

Corrosion Protection ◽

Surface Potential ◽

Electrochemical Impedance ◽

Substrate Surface ◽

Titanium Substrate ◽

Tio2 Surface ◽

Corrosion Properties ◽

Inner Surface ◽

Before And After ◽

Titanium Material

In this study, the surface properties of Ti/TiO2 substrate before and after the adsorption of polyelectrolytes were investigated. As model polyelectrolytes, strongly charged polycation poly(diallyldimethylammonium) (PDADMA) and strongly charged polyanion poly(4-styrenesulfonate) (PSS) were used. Initially, the bare titanium substrate was characterized by means of ellipsometry, atomic force microscopy (AFM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and measurements of inner surface potential using crystal electrode (CrE). It was shown that the substrate surface is very smooth with the roughness of 3.5 nm and oxide layer thickness of 3.8 nm. After the adsorption of PDADMA and PSS, polyelectrolyte-coated titanium surface was examined using the above-mentioned methods under the same conditions. It was found that both PDADMA cations and PSS anions form a stable polymeric nanofilm on Ti/TiO2 surface that partially covers the surface, without significant impact on the surface roughness. The corrosion protection effectiveness values indicate that the corrosion properties were greatly enhanced upon polyion adsorption and polyelectrolyte coating formation on the flat TiO2 surface. The obtained results were additionally confirmed by inner surface potential measurements. According to the methods employed, PDADMA nanofilm modification offers enhanced corrosion protection to the underlying titanium material in sodium chloride electrolyte solution.

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A SEM and Light Microscope Study of the Epidermal Leaf Structures of the Carnivorous Plant, Sarracenia purpurea, L.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065833 ◽

1971 ◽

Vol 29 ◽

pp. 358-359

Author(s):

B. J. Panessa ◽

J. F. Gennaro

Keyword(s):

Methylene Blue ◽

Toluidine Blue ◽

Outer Surface ◽

Microscope Study ◽

Light Microscope ◽

Carnivorous Plant ◽

Sarracenia Purpurea ◽

Inner Surface

Tissue from the hood and sarcophagus regions were fixed in 6% glutaraldehyde in 1 M.cacodylate buffer and washed in buffer. Tissue for SEM was partially dried, attached to aluminium targets with silver conducting paint, carbon-gold coated(100-500Å), and examined in a Kent Cambridge Stereoscan S4. Tissue for the light microscope was post fixed in 1% aqueous OsO4, dehydrated in acetone (4°C), embedded in Epon 812 and sectioned at ½u on a Sorvall MT 2 ultramicrotome. Cross and longitudinal sections were cut and stained with PAS, 0.5% toluidine blue and 1% azure II-methylene blue. Measurements were made from both SEM and Light micrographs.The tissue had two structurally distinct surfaces, an outer surface with small (225-500 µ) pubescent hairs (12/mm2), numerous stoma (77/mm2), and nectar glands(8/mm2); and an inner surface with large (784-1000 µ)stiff hairs(4/mm2), fewer stoma (46/mm2) and larger, more complex glands(16/mm2), presumably of a digestive nature.

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Gastric Ulcers Produced by Cisplatin

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099337 ◽

1981 ◽

Vol 39 ◽

pp. 582-583

Author(s):

S.K. Aggarwal ◽

J. San Antonio

Keyword(s):

Electron Microscopy ◽

Single Dose ◽

Side Effects ◽

Antitumor Agent ◽

Gastric Ulcers ◽

Enzyme Cytochemistry ◽

Intestinal Toxicity ◽

Ovarian Cancers ◽

Inner Surface

Cisplatin (cis-dichlorodiammineplatinum(II)) a potent antitumor agent is now available for the treatment of testicular and ovarian cancers. It is however, not free from its serious side effects including nephrotoxicity, gastro intestinal toxicity, myelosuppression, and ototoxicity. Here we now report that the drug produces peculiar bloating of the stomach in rats and induces acute ulceration.Wistar-derived rats weighing 200-250 g were administered cisplatin(9 mg/kg) ip as a single dose in 0.15 M NaCl. After 3 days the animals were sacrificed by decapitation. The stomachs were removed, the contents analyzed for pepsin and acidity. The inner surface was examined with a dissecting microscope after a moderate stretching for ulcers. Affected areas were fixed and processed for routine electron microscopy and enzyme cytochemistry.The drug treated animals kept on food and water consistently showed bloating and lesions (Fig. 1) with a frequency of 6-70 ulcers in the rumen section of the stomachs.

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The effects of surface absorbed monolayer microdiffraction patterns

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105461 ◽

1988 ◽

Vol 46 ◽

pp. 680-681

Author(s):

M. Pan ◽

J.M. Cowley

Keyword(s):

Surface Potential ◽

Electron Probe ◽

Potential Distribution ◽

Crystal Surface ◽

Normal Direction ◽

Surface Image ◽

Extended Surface ◽

Gas Molecules ◽

Surface Nature ◽

Electron Microdiffraction

Electron microdiffraction patterns, obtained when a small electron probe with diameter of 10-15 Å is directed to run parallel to and outside a flat crystal surface, are sensitive to the surface nature of the crystals. Dynamical diffraction calculations have shown that most of the experimental observations for a flat (100) face of a MgO crystal, such as the streaking of the central spot in the surface normal direction and (100)-type forbidden reflections etc., could be explained satisfactorily by assuming a modified image potential field outside the crystal surface. However the origin of this extended surface potential remains uncertain. A theoretical analysis by Howie et al suggests that the surface image potential should have a form different from above-mentioned image potential and also be smaller by several orders of magnitude. Nevertheless the surface potential distribution may in practice be modified in various ways, such as by the adsorption of a monolayer of gas molecules.

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