Whats the relation between zeta potential and stability of. Potential energy hard sphere h depletion interaction. The negative charge may be quantified by zeta potential or streaming potential measures. The colloidal system is stable when a dominant role is played by the forces causing the mutual repulsion of the particles. Guidelines are available in other standards, and there exists a wealth of information in texts and publications. Typically, the higher the zeta potential, the more stable the colloid. Control of colloid stability through zeta potential zeta potential is a measure of the electrical force that exists between atoms, molecules, particles, suspensoids, cells, etc. We have used r 250 nm and a hamaker constant of h 5. In its original version, however, the dlvo theory includes the additional step to calculate aggregation rates. Apr 01, 20 the parameter that is used to describe this real, measurable potential is the zeta potential. It can be used to optimize the formulations of suspensions and emulsions.
Zeta potential in colloid sciencetheory and application. Ep11 electric double layer edl and dlvo forces nano 202 ucsd. Based on lectures given at the highly successful bristol colloid centre spring school, colloid science. Zeta potential is a scientific term for electrokinetic potential in colloidal dispersions. Zeta potential and colloid chemistry eric olson abstract. In order to discuss zeta potential in some detail, it is imperative to begin by defining the particles and systems to which zeta potential pertains. Principles, methods and applications characteristic features of surfactantsclassification and applications of additional resources for colloid science. The electrostatic potential on that surface is called the zeta potential and it is that potential which is measured, when one measures the velocity of the particles in a d. The zeta potential in colloid science is the overall charge a particle acquires in a specific medium. Zeta potential represents a basic law of nature, and it plays a vital role in all forms of plant and animal life. Zeta potential in colloid sciencetheory and application, by r.
Heat treatment of milk between 90 c30 min and 5 c50 min had no significant effect on zeta potential. Zetapotential measurement using the smoluchowski equation. Although zeta potential is an intermediate value, it is sometimes considered to be more significant than surface potential as far as electrostatic repusion is concerned. Since zeta potential is not equal to the electric surface potential in a double layer or to the stern potential, it is often the only value that can be used to describe doublelayer properties of. From a theoretical viewpoint, the zeta potential is the electric potential in the interfacial double layer at the location of the slipping plane relative to a point in the bulk fluid away. The higher is an absolute value of the zeta potential, the greater the probability that the studied suspension will be stable.
Zeta potential analyses is a technique for determining the dispersion stability of nps in solution fig. Zeta potential can be quantified by tracking the colloidal particles through a microscope as they migrate in a voltage field. In the colloidal chemistry literature, it is usually denoted using the greek letter zeta. The magnitude of the zeta potential gives an indication of the potential stability of the colloidal system. As these parameters are related to the colloid charge, we also briefly discuss the mechanism of charge neutralization. The potential difference electroosmosis and allied phenomena between the fixed part and freely mobile portions of double layer known as zeta potential i. Suspensions of liquids form the basis of a wide variety of systems of scientific and technological importance including paints, inks, ceramics, cosmetics, soils, biological cells, and many food preparations. Nanomedicine formulations typically represent a multifunctional and multicomponent system. The higher value of zeta potential increase the particles stability.
These parameters will be used in all other examples discussed below. Colloid science is the study of systems involving small particles of one substance suspended in another. Jun 04, 2014 the zeta potential measurements allow to estimate of colloidal suspension stability. Zeta potential and colloid chemistry eric olson abstract the us food and drug administration often requests the measurement of zeta potential. A colloidal system consists of a dispersed phase that is distributed uniformly in a continuous phase. Over 10 million scientific documents at your fingertips. These surface potentials could be obtained in experiments from zeta potential measurements for the bare wall and for one saturated with patches. Apr 05, 2010 the streaming potential of mica covered by monodisperse latex particles was measured using the parallelplate channel, fourelectrode cell.
What is zeta potential in colloid science overall charge. It is also an aid in predicting longterm stability. Principles and applications, issn 03059723 0123619610, 9780123619617 moral problems in medicine a practical coursebook, palmer michael, michael palmer, sep 1, 2005, medical, 192 pages. The surface charge on the swnt micelles, as measured by the. Effect of mixing water types on the timedependent zeta potential of portland cement paste article pdf available in science and engineering of composite materials 203 august 20 with 431 reads. Simplifying the measurement of ze ta potential using m3pals, technical note available from. From a theoretical viewpoint, the zeta potential is the electric potential in the. Principles and applications covers the concept of the zeta potential in. A standard reference material for the measurement of. Zeta potential is measured in liquidliquid or solidliquid colloidal systems. Simplifying the measurement of zeta potential using m3pals, technical note available from. The zeta potential of casein micelles was observed to increase with increase in temperature from 10 to 50 c and to decrease with decrease in ph. The zeta potential of latex bearing amidine charged groups was regulated by the addition of nacl 10.
Zeta potential is a very important interfacial electrokinetic property to a huge number of natural phenomena, such as electrode kinetics, electrocatalysis, corrosion, adsorption, crystal growth, colloid stability and flow characteristics of colloidal suspensions and electrolyte solutions through porous media and microchannels. Zeta potential is a physical property which is exhibited by any particle in suspension. The dispersed phase contains particles or micelles that have a linear dimension between 1 nm and 1. In order to explain the obtained zeta potential dependencies in the presence of ionic polyamino acids, it is necessary to analyze the relations between the amount of polymer adsorption and the dissociation degree of the studied polyamino acids. When the zeta potential equals zero, the colloid will precipitate into a solid.
In chemistry, a colloid is a mixture in which one substance of microscopically dispersed insoluble or soluble particles is suspended throughout another substance. Journal of colloid and interface science 449 2015 443451. The zeta potential is an important parameter for a number of applications including characterization of biomedical polymers 1,2, electrokinetic transport of. Riddick introduction excerpts and important material glossary. The book discusses the charge and potential distribution at interfaces. If all the particles have a large negative or positive zeta potential they will repel each other and there is dispersion stability.
Coagulation process is usually explained by charge neutralization mechanism. Control of colloid stability through zeta potential by thomas m. In prior literature, it is usually denoted using the greek letter zeta. However, owing to a variety of factors, this is not necessarily the case. In the colloidal chemistry literature, it is usually denoted using the greek letter zeta, hence.
Zeta potential is a measure of the magnitude of the electrostatic or charge repulsionattraction between particles and is one of the fundamental parameters known to affect stability. Aug 04, 2015 zeta potential part 17cbse grade 12 chemistryunit 5. Principles and applications covers the concept of the zeta potential in colloid chemical theory. Its a measure of the electrical charge of particles are that are suspended in liquid. Knowledge of the zeta potential can reduce the time needed to produce trial formulations. The determination of the zeta potential of casein micelles. Fo r example red blood cells suspended in isotonic saline solution essentially 0. Lyklema j, fundamentals of interface and colloid science. Lectures are collated and presented in a coherent and logical text on practical colloid science. Sometimes the dispersed substance alone is called the colloid. Comparison of the zeta potential with the diffuse layer potential from charge titration.
Prior to the advent of streaming current monitors, zeta meters were the primary instruments for measuring electrokinetic. L download it once and read it on your kindle device, pc, phones or tablets. Understanding zeta potential in suspension youtube. Use features like bookmarks, note taking and highlighting while reading zeta potential in colloid science. The streaming potential of mica covered by monodisperse latex particles was measured using the parallelplate channel, fourelectrode cell. Principles and applications colloid sciences series kindle edition by hunter, robert j. Zeta potential is a measure of the magnitude of the repulsion or attraction between particles. The zeta potential of our samples was determined with a zeta potential analyzer from. Its measurement brings detailed insight into the causes of dispersion, aggregation or flocculation, and can be applied to improve the formulation of dispersions. Zeta potential that is less negative than 15 mv typically represents the beginnings of agglomeration of particles. Principles and applications colloid sciences series. Zeta potential of mica covered by colloid particles.
Application of the zeta potential measurements to explanation. Dvlo theory suggests that the stability of a colloidal system is determined by the sum. Colloid science principles methods and applications. In cell biology, the concept of zeta potential has been used to study cell biological activation, cell agglutination and cell. The zeta potential of the particles is the electric potential at the boundary of the double layer on the particle surface. Download pdf colloid science free online new books in. Pdf effect of mixing water types on the timedependent. Principles, methods and applications provides a thorough introduction to colloid science for industrial chemists, technologists and engineers.
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