Effect of exposure to growth media on size and surface charge of silica based Stöber nanoparticles: a DLS and ζ-potential study

<p>Tunable resistive pulse sensing (TRPS) is a particle-by-particle analysis technique combining the Coulter principle with size-tunable pores. TRPS can be used to characterize biological and synthetic particles 50 nm - 20 µm in diameter. Information is obtained from the resistive pulse signal, a transient change in ionic current observed when a particle passes through the pore. TRPS has been shown to provide excellent resolution and accuracy for measuring particle size and concentration as well as providing information about particle charge. TRPS is therefore applicable to many industrial and fundamental research areas involving aptamers, drug delivery particles, extracellular vesicles and other biological particle types. Advancement of this technology requires a better understanding of the technique, particularly in the area of particle surface charge measurement and this Thesis helps to provide that understanding. In this work, firstly particle ζ-potential measurement using TRPS was investigated. A number of different measurement methods are presented and the uncertainties associated with each method are outlined. The ζ-potential for a variety of particles with different surface charges were measured in a range of electrolytes. Particle ζ-potential measurements were then improved upon with the addition of streaming potential measurements to measure the pore surface charge. The ζ-potential of the pore surface, which makes a significant contribution to particle ζ-potential calculations, was measured using a set up which works alongside the qNano. Streaming potential measurements were also used to investigate changes in the pore surface charge following application of number of different chemical coatings. The volume of data collected and detail of analysis in this work (including uncertainties) is unprecedented in TRPS ζ potential measurements. Biphasic pulses arising from the charge on the particles were investigated. The pulse is conventionally resistive, but biphasic pulses which include both resistive and conductive components are significant for less than 50 mM salt concentrations when measuring 200 nm particles. The experimental variables investigated include the concentration of the electrolyte, particle charge, pore size, applied voltage, and the direction of particlemotion. Conductive pulse size was seen to decrease with increasing electrolyte concentration and pore size and increase with applied voltage. A linear relationship was found between conductive pulse magnitude and particle surface group density. The influence of direction of motion on conductive pulses was consistent with concentration polarization of an ion selective pore. Biphasic pulses were also seen to affect conventional TRPS particle size measurements. Finally, size distribution broadening due to varying particle trajectories was investigated. Pulse size distributions for monodisperse particles became broader when the pore size was increased and featured two distinct peaks. Relatively large pulses are produced by particles with trajectories passing near to the edge of the pore. Other experiments determined that pulse size distributions are independent of applied voltage but broaden with increasing pressure applied across the membrane.</p>

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The ζ-Potential of Kaolinite Particles

Australian Journal of Chemistry ◽

10.1071/ch9560450 ◽

1956 ◽

Vol 9 (4) ◽

pp. 450 ◽

Cited By ~ 30

Author(s):

N Street ◽

AS Buchanan

Keyword(s):

Charge Density ◽

Surface Charge ◽

Electrophoretic Mobility ◽

Surface Charge Density ◽

Considerable Increase ◽

Ionic Species ◽

Ζ Potential ◽

Potentiometric Titrations ◽

Kaolinite Suspension

Electrophoretic mobility measurements, and both conductometric and potentiometric titrations, were carried out on a kaolinite suspension throughout its neutralization by various bases. The concentration of the ionic species present was calculated from the conductometric and potentiometric titrations, and the true ζ-potential calculated from the electrophoretic mobility by Stigter and Mysels's (1955) method. The results indicate that a discontinuity exists in the adsorption of ions in the vicinity of pH 6.5-7.0 causing a considerable increase in the surface charge density of the particles.

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Dependence of ζ-Potential upon Particle Size and Capillary Radius at Streaming Potential Study in Nonaqueous Media

Bulletin of the Chemical Society of Japan ◽

10.1246/bcsj.44.3242 ◽

1971 ◽

Vol 44 (12) ◽

pp. 3242-3245 ◽

Cited By ~ 18

Author(s):

Ayao Kitahara ◽

Tadashi Fujii ◽

Seiji Katano

Keyword(s):

Particle Size ◽

Streaming Potential ◽

Nonaqueous Media ◽

Ζ Potential ◽

Capillary Radius ◽

Potential Study

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Electrokinetics of Carbonate/Brine Interface in Low-Salinity Waterflooding: Effect of Brine Salinity, Composition, Rock Type, and pH on ?-Potential and a Surface-Complexation Model

SPE Journal ◽

10.2118/181745-pa ◽

2016 ◽

Vol 22 (01) ◽

pp. 53-68 ◽

Cited By ~ 123

Author(s):

Hassan Mahani ◽

Arsene Levy Keya ◽

Steffen Berg ◽

Ramez Nasralla

Keyword(s):

Surface Charge ◽

Carbonate Rock ◽

Rock Type ◽

Surface Complexation ◽

Surface Complexation Model ◽

Ζ Potential ◽

Low Salinity ◽

Ph Values ◽

Different Types ◽

Brine Salinity

Summary Laboratory studies have shown that wettability of carbonate rock can be altered to a less-oil-wetting state by manipulation of brine composition and reduction of salinity. Our recent study (Mahani et al. 2015b) suggests that surface-charge alteration is likely to be the driving mechanism of the low-salinity effect in carbonates. Various studies have already established the sensitivity of carbonate-surface charge to brine salinity, pH value, and potential-determining ions in brines. However, in the majority of the studies, single-salt brines or model-carbonate rocks have been used and it is fairly unclear how natural rock reacts to reservoir-relevant brine as well as successive brine dilution; whether different types of carbonate-reservoir rocks exhibit different electrokinetic properties; and how the surface-charge behavior obtained at different brine salinities and pH values can be explained. This paper presents a comparative study aimed at gaining more insight into the electrokinetics of different types of carbonate rock. This is achieved by ζ-potential measurements on Iceland spar calcite and three reservoir-related rocks—Middle Eastern limestone, Stevns Klint chalk, and Silurian dolomite outcrop—over a wide range of salinity, brine composition, and pH values. With a view to arriving at a more-tractable approach, a surface-complexation model (SCM) implemented in PHREEQC software (Parkhurst and Appelo 2013) is developed to relate our understanding of the surface reactions to measured ζ-potentials. It was found that regardless of the rock type, the trends of ζ-potentials with salinity and pH are quite similar. For all cases, the surface charge was found to be positive in high-salinity formation water (FW), which should favor oil-wetting. The ζ-potential successively decreased toward negative values when the brine salinity was lowered to seawater (SW) level and diluted SW. At all salinities, the ζ-potential showed a strong dependence on pH, with positive slope that remained so even with excessive dilution. The sensitivity of the ζ-potential to pH change was often higher at lower salinities. The existing SCMs cannot predict the observed increase of ζ-potential with pH; therefore, a new model is proposed to capture this feature. According to modeling results, formation of surface species, particularly >CaSO4− and to a lower extent >CO3Ca+ and >CO3Mg+, strongly influence the total surface charge. Increasing the pH turns the negatively charged moiety >CaSO4− into both negatively charged >CaCO3− and neutral > CaOH entities. (Note that throughout this paper, the symbol > indicates surface complexes.) This substitution reduces the negative charge of the surface. The surface concentration of >CO3Ca+ and >CO3Mg+ moieties changes little with change of pH. Nevertheless, besides similarities in ζ-potential trends, there exist notable differences in terms of magnitude and the isoelectric point (IEP), even between carbonates that are mainly composed of calcite. Among all the samples, chalk particles exhibited the most negative surface charges, followed by limestone. In contrast to this, dolomite particles showed the most positive ζ-potential, followed by calcite crystal. Overall, chalk particles exhibited the highest surface reactivity to pH and salinity change, whereas dolomite particles showed the lowest.

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Listeria monocytogenes Scott A: Cell Surface Charge, Hydrophobicity, and Electron Donor and Acceptor Characteristics under Different Environmental Growth Conditions

Applied and Environmental Microbiology ◽

10.1128/aem.65.12.5328-5333.1999 ◽

1999 ◽

Vol 65 (12) ◽

pp. 5328-5333 ◽

Cited By ~ 149

Author(s):

Romain Briandet ◽

Thierry Meylheuc ◽

Catherine Maher ◽

Marie Noëlle Bellon-Fontaine

Keyword(s):

Listeria Monocytogenes ◽

Cell Surface ◽

Physicochemical Properties ◽

Surface Charge ◽

Electron Donor ◽

Growth Temperature ◽

Growth Media ◽

A Cells ◽

Donor And Acceptor ◽

Electron Donor And Acceptor

ABSTRACT We determined the variations in the surface physicochemical properties of Listeria monocytogenes Scott A cells that occurred under various environmental conditions. The surface charges, the hydrophobicities, and the electron donor and acceptor characteristics of L. monocytogenes Scott A cells were compared after the organism was grown in different growth media and at different temperatures; to do this, we used microelectrophoresis and the microbial adhesion to solvents method. Supplementing the growth media with glucose or lactic acid affected the electrical, hydrophobic, and electron donor and acceptor properties of the cells, whereas the growth temperature (37, 20, 15, or 8°C) primarily affected the electrical and electron donor and acceptor properties. The nonlinear effects of the growth temperature on the physicochemical properties of the cells were similar for cells cultivated in two different growth media, but bacteria cultivated in Trypticase soy broth supplemented with 6 g of yeast extract per liter (TSYE) were slightly more hydrophobic than cells cultivated in brain heart infusion medium (P < 0.05). Adhesion experiments conducted withL. monocytogenes Scott A cells cultivated in TSYE at 37, 20, 15, and 8°C and then suspended in a sodium chloride solution (1.5 × 10−1 or 1.5 × 10−3 M NaCl) confirmed that the cell surface charge and the electron donor and acceptor properties of the cells had an influence on their attachment to stainless steel.

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Interaction between Penicillins and Human Serum Albumin: A ζ-Potential Study

Langmuir ◽

10.1021/la9912904 ◽

2000 ◽

Vol 16 (17) ◽

pp. 6795-6800 ◽

Cited By ~ 22

Author(s):

Pablo Taboada ◽

Victor Mosquera ◽

Juan M. Ruso ◽

Felix Sarmiento ◽

Malcolm N. Jones

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Ζ Potential ◽

Potential Study

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Advancement of Measurement Techniques for Tunable Resistive Pulse Sensing

10.26686/wgtn.17060669.v1 ◽

2021 ◽

Author(s):

◽

Eva Weatherall

Keyword(s):

Surface Charge ◽

Pore Size ◽

Applied Voltage ◽

Particle Surface ◽

Streaming Potential ◽

Pore Surface ◽

Size Distributions ◽

Ζ Potential ◽

Resistive Pulse ◽

Tunable Resistive Pulse Sensing

<p>Tunable resistive pulse sensing (TRPS) is a particle-by-particle analysis technique combining the Coulter principle with size-tunable pores. TRPS can be used to characterize biological and synthetic particles 50 nm - 20 µm in diameter. Information is obtained from the resistive pulse signal, a transient change in ionic current observed when a particle passes through the pore. TRPS has been shown to provide excellent resolution and accuracy for measuring particle size and concentration as well as providing information about particle charge. TRPS is therefore applicable to many industrial and fundamental research areas involving aptamers, drug delivery particles, extracellular vesicles and other biological particle types. Advancement of this technology requires a better understanding of the technique, particularly in the area of particle surface charge measurement and this Thesis helps to provide that understanding. In this work, firstly particle ζ-potential measurement using TRPS was investigated. A number of different measurement methods are presented and the uncertainties associated with each method are outlined. The ζ-potential for a variety of particles with different surface charges were measured in a range of electrolytes. Particle ζ-potential measurements were then improved upon with the addition of streaming potential measurements to measure the pore surface charge. The ζ-potential of the pore surface, which makes a significant contribution to particle ζ-potential calculations, was measured using a set up which works alongside the qNano. Streaming potential measurements were also used to investigate changes in the pore surface charge following application of number of different chemical coatings. The volume of data collected and detail of analysis in this work (including uncertainties) is unprecedented in TRPS ζ potential measurements. Biphasic pulses arising from the charge on the particles were investigated. The pulse is conventionally resistive, but biphasic pulses which include both resistive and conductive components are significant for less than 50 mM salt concentrations when measuring 200 nm particles. The experimental variables investigated include the concentration of the electrolyte, particle charge, pore size, applied voltage, and the direction of particlemotion. Conductive pulse size was seen to decrease with increasing electrolyte concentration and pore size and increase with applied voltage. A linear relationship was found between conductive pulse magnitude and particle surface group density. The influence of direction of motion on conductive pulses was consistent with concentration polarization of an ion selective pore. Biphasic pulses were also seen to affect conventional TRPS particle size measurements. Finally, size distribution broadening due to varying particle trajectories was investigated. Pulse size distributions for monodisperse particles became broader when the pore size was increased and featured two distinct peaks. Relatively large pulses are produced by particles with trajectories passing near to the edge of the pore. Other experiments determined that pulse size distributions are independent of applied voltage but broaden with increasing pressure applied across the membrane.</p>

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Density of surface charge is a more predictive factor of the toxicity of cationic carbon nanoparticles than zeta potential

Journal of Nanobiotechnology ◽

10.1186/s12951-020-00747-7 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Maud Weiss ◽

Jiahui Fan ◽

Mickaël Claudel ◽

Thomas Sonntag ◽

Pascal Didier ◽

...

Keyword(s):

Charge Density ◽

Surface Charge ◽

Airway Inflammation ◽

Surface Charge Density ◽

Airway Epithelial Cells ◽

Mucus Production ◽

Ζ Potential ◽

Viability Loss

Abstract Background A positive surface charge has been largely associated with nanoparticle (NP) toxicity. However, by screening a carbon NP library in macrophages, we found that a cationic charge does not systematically translate into toxicity. To get deeper insight into this, we carried out a comprehensive study on 5 cationic carbon NPs (NP2 to NP6) exhibiting a similar zeta (ζ) potential value (from + 20.6 to + 26.9 mV) but displaying an increasing surface charge density (electrokinetic charge, Qek from 0.23 to 4.39 µmol/g). An anionic and non-cytotoxic NP (NP1, ζ-potential = − 38.5 mV) was used as control. Results The 5 cationic NPs induced high (NP6 and NP5, Qek of 2.95 and 4.39 µmol/g, respectively), little (NP3 and NP4, Qek of 0.78 and 1.35 µmol/g, respectively) or no (NP2, Qek of 0.23 µmol/g) viability loss in THP-1-derived macrophages exposed for 24 h to escalating NP dose (3 to 200 µg/mL). A similar toxicity trend was observed in airway epithelial cells (A549 and Calu-3), with less viability loss than in THP-1 cells. NP3, NP5 and NP6 were taken up by THP-1 cells at 4 h, whereas NP1, NP2 and NP4 were not. Among the 6 NPs, only NP5 and NP6 with the highest surface charge density induced significant oxidative stress, IL-8 release, mitochondrial dysfunction and loss in lysosomal integrity in THP-1 cells. As well, in mice, NP5 and NP6 only induced airway inflammation. NP5 also increased allergen-induced immune response, airway inflammation and mucus production. Conclusions Thus, this study clearly reveals that the surface charge density of a cationic carbon NP rather than the absolute value of its ζ-potential is a relevant descriptor of its in vitro and in vivo toxicity.

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