Ppt microemulsions powerpoint presentation free to view. Properties and applications of microemulsions by john klier, christopher j. To disperse two immiscible liquids, one needs a third component, namely, the emulsi. Thus, for lipophilic drug compounds that exhibit dissolution ratelimited absorption, these systems. Fluorescence measurements of the hydrophobic probe mainly depend on the polarity of the medium and hence in bicontinuous microemulsions it is a good indication of the polarity of the microenvironment in the microemulsion structure. Microemulsions are amphiphile aided thermodynamically stable. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. If so, share your ppt presentation slides online with. Drug delivery through microemulsions is a promising area for continued research with the aim of achieving controlled release with enhanced bioavailability and for drug targeting to various. Microemulsions are really single phase systems in which the structure contains fusioned oil. Microemulsions are shown to be effective dermal delivery mechanism for several active ingredients for pharmaceutical and cosmetic applications. Droplet formation is facilitated by the addition of surfactants and often also co surfactants. The main driving force for microemulsion formation is the ultra low interfacial tension, which is usually achieved by the use of two or more emulsifiers scos. Introduction n search of safe and effective therapy, the development of new drugs has been the common practice historically.
The microemulsion definition provided by danielson and lindman in 1981 will be used as the point of reference. Microemulsion, theory, preparation, phase behaviour, structure, properties, application. However, the situation of petroleum industries in many countries needs much concern in improving the oil recovery technique. The adobe flash plugin is needed to view this content. In particular, the high solubilizing power of microemulsions and microemulsion systems for organic and inorganic com.
Properties and applications provides a complete and systematic assessment of all topics affecting microemulsion performanc. Ocular drug delivery aswani dutt vadlapudi, kishore cholkar, supriya reddy dasari, and ashim k. More thermodynamically stable than macro emulsions. Apart from being more commercially viable due to its lower energy requirements, microemulsions are also attracting the interest of researchers due to their potential as drug delivery vehicles, in 1 chandra, a1992. The trend of growing interest in alternative source of energy focuses on renewable products worldwide. Propofol possesses several favorable characteristics, including an antiemetic effect and rapid emergence from unconsciousness with minimal residual drowsiness. B and c cartoon demonstrating the relative particle sizes of the macroemulsion b and microemulsion c. Properties and applications provides a complete and systematic assessment of all topics affecting microemulsion performance and discusses the fundamental characteristics, t. Introduction to macro and microemulsions acs symposium.
Microemulsion provides very efficient approach in oil extraction from oilseed on. Various propofol microemulsions were assessed for their potential to cause in vitro hemolysis of heparinized fresh human whole blood. Microemulsions based transdermal drug delivery systems. Winner of the standing ovation award for best powerpoint templates from presentations magazine. Formulation and characterization of microemulsion system.
This book deals first with the commercial history of microemulsions, from the discovery of carnauba wax emulsions to polymer emulsions. Anna zieli skajurek, joanna reszczy ska, ewelina grabowska. Microemulsions or micellar emulsion are dynamic system in which the interface is continuously and spontaneously fluctuating 31. These latter hold the key to the effect of humidity on skin properties and are the essence of.
Basic aspects of microemulsion microemulsion are fluid, transparent, thermodynamically stable oil and water system and stabilized by a surfactant usually in conjunction with cosurfactant. Characterization of microemulsions necessarily begins with the elucidation of the phase behavior, where, in the most simple form, oil, water, and surfactant are mixed in different molar ratios, and the formed phases are tracked. Pdf microemulsions mes have attracted much interest over the past years as. Dec 15, 2008 the effective use of microemulsions has increased dramatically during the past few decades as major industrial applications have expanded in a variety of fields. A shown in the photograph is an opaque, white macroemulsion macro and a clear, colorless microemulsion micro of propofol. Microemulsions have low viscosity compared to emulsions. Microemulsions are potentially quite powerful alernative carrier system for delivery because of high solubilization capacity, transparency, thermodynamic stability, ease of preparation, and high diffusion and absorption rates through skin, when compared to solvent without the surfactant system.
During emulsion formation, the deformation is opposed by the laplace pressure. The role of interfacial film of surfactants in the formation of these systems has been highlighted. Design and evaluation of microemulsions for improved. Enhancement of antioxidant and skin moisturizing effects. Since the discovery of microemulsions by jack h schulman, there has been huge progress made in applying microemulsion systems in plethora of research and industrial process. Microemulsions are optically isotropic systems consisting of water, oil and amphiphile.
Microemulsions are thermodynamically stable dispersions of oil and water stabilized by a surfactant and, in many cases, also a cosurfactant. Sep 24, 2014 the trend of growing interest in alternative source of energy focuses on renewable products worldwide. Structurally, they are divided in to oil in water ow, water in oil wo and bicontinuous microemulsions. And they can be known as modern colloidal drug delivery system. Microemulsions is the property of its rightful owner. These metrics are regularly updated to reflect usage leading up to the last few days. Microemulsions, on the other hand, are thermodynamically stable. Ppt microemulsions powerpoint presentation free to view id. Acaadeemmiiccsscciieenncessinternational journal of pharmacy. Surfactant associates emulsions and microemulsions.
In several regions of the phase diagram, single phases exist in one. However, it involved a long gestation period in terms of time, efforts, and huge cost. For example, ow and wo microemulsions show newtonian behavior over a wide range of shears, while the bicontinuous phase may undergo breakage upon medium shear forces, leading to thinning. In order to prepare wo microemulsions, a cyclohexane was used as the oil phas e and a mixture of poly oxyethylene 5 nonyle phenol ether np5, chemical purity and poly oxyethylene 9 nonyle phenol ether with weight ratio 1. Oil in water microemulsions wherein oil droplets are dispersed in the continuous aqueous phase. Microemulsions are thermodynamically stable, and their formation is facilitated by the ultralow interfacial tension of these systems, which leads to the formation of extremely small droplets of the dispersed phase. A microemulsion is a thermodynamically stable fluid. Acaadeemmiiccsscciieenncessinternational journal of. While some people insist that microemulsions must be transparent, that is not really a critical part of their description. Worlds best powerpoint templates crystalgraphics offers more powerpoint templates than anyone else in the world, with over 4 million to choose from. Microemulsions in food industry uses and applications.
Because of the small particle sizes, microemulsions appear as clear. Microemulsions potential carrier for improved drug delivery. The term microemulsion refers to a thermodynamically stable isotropically clear dispersion of two immiscible liquids, such as oil and water. In addition, microemulsions are thermodynamically stable and spontaneously forming, making them easy to prepare. This book provides an assessment of some issues influencing the characteristics and performance of the microemulsions, as well as their main types of applications. Theory and practice covers the development of the theory and practice of microemulsion systems. Important uses and applications of microemulsions in food industry will also be discussed.
Pdf in the past twenty five years, microemulsions have been the focus of extensive. Historical background definition composition of microemulsion major goals advantages disadvantages macroemulsion vs microemulsion types of microemulsions preparation methods of microemulsions equipments used for the preparation of microemulsions formation of. This book is divided into seven chapters that explore the physics and chemistry of microemulsions. Chemical method, especially microemulsion flooding, plays an important role in enhanced oil recovery technique due to its ability to reduce interfacial tension between. Microemulsions are thermodynamically stable system and allows selfemulsification of the system.
The effective use of microemulsions has increased dramatically during the past few decades as major industrial applications have expanded in a variety of fields. Microemulsions a brief introduction 5 microemulsions one must consider all kind of the interactions existing between the components present in the system, i. Theyll give your presentations a professional, memorable appearance the kind of sophisticated look that todays audiences expect. This chapter is devoted to another important property of surfactants, that of stabilization of wateroil films and formation of microemulsions. In chapter 1 a short introduction about the background, various aspects and applications. The for mation of final emulsion droplets can be viewed as the stepwise pro cess. Enhancement of antioxidant and skin moisturizing effects of. Emulsions and microemulsions are both stable dispersions of oilinwater or waterinoil. Our new crystalgraphics chart and diagram slides for powerpoint is a collection of over impressively designed datadriven chart and editable diagram s guaranteed to impress any audience.
Microemulsions, surfactants, cosurfactants, thermodynamic stability, phase behavior, novel carriers. Microemulsions mes represent a promising delivery system for pharmaceuticals and cosmeceuticals due to its numerous advantages over the existing conventional formulations. Discusses important issues related to enzymatic reactions and nanoparticle formation. Describe various barriers to ocular drug delivery and constraints with. Temperature range in which an ow microemulsions inverts to a wo type. In the short course we will give a systematic introduction to the mechanisms of kinetic stabilization of macroemulsions, show how macroemulsions are related. Microemulsions are mixtures of oil, surfactant, and water that form spontaneously on bringing the three components together 69. Microemulsions are readily distinguished from normal emulsions by their transparency, low viscosity and more fundamentally their thermodynamic stability. Microemulsions are usually characterised by ternary phase diagrams, which three edges are the components of a microemulsion, namely, oil, water and surfactant. The particle size of microemulsions ranges from about 10300 nm. Mes are widely investigated for preparing personal care products with superior. Hydrogels, microemulsion, nanoparticles, organogels, polymerization.
Photograph and cartoons of a macroemulsion and microemulsion of propofol. Because of the small particle sizes, microemulsions appear as clear or translucent solutions. Emulsions part 3 microemulsions miniemulsions remarks to. Continue microemulsions are dispersions of nanometersized droplets of an immiscible liquid within another liquid.
Microemulsions this chapter is devoted to another important property of surfactants, that of stabilization of wateroil films and formation of microemulsions. Chart and diagram slides for powerpoint beautifully designed chart and diagram s for powerpoint with visually stunning graphics and animation effects. Tween 20, 40, 60, and 80 were used separately as surfactant with methanol, ethanol, 1propanol, 1butanol or 1pentanol as cosurfactant, and ipp as oil phase to prepare various microemulsions. Construction of phase diagram is a useful approach to study the complex series of interactions that can occur when different components microemulsions as promising delivery systems. Emulsions are stable dispersions of immiscible liquids, but they are not thermodynamically stable. Therefore, the disruption of droplets is a critical step in the process of emulsification.
The aqueous phase may contain salt s andor other ingredients, and the oil may actually be a complex mixture of different hydrocarbons and olefins. Nov 21, 2014 the microemulsion definition provided by danielson and lindman in 1981 will be used as the point of reference. In the case of oilinwater microemulsions, the steadystate fluorescence technique was successfully applied 36. Generally obtained by gentle mixing of ingredients. Microemulsions are amphiphile aided thermodynamically stable oil in water ow or water in oil wo dispersions. A potential novel drug delivery system jaspreet kaur saini 1, ujjwal nautiyal 1, senthil kumar m 1, devendra singh 2, firoz anwar 3 1department of pharmaceutics, himachal institute of pharmacy, paonta sahib, himachal pradesh, india.
Microemulsions act as supersolvents for drug, can solubilise both hydrophilic and lipophilic drugs including drugs that are insoluble in both aqueous and hydrophobic solvents. Introduction microemulsions are thermodynamically stable, fluid, optically clear dispersions of two immiscible liquids such as oil and water. Thus, for lipophilic drug compounds that exhibit dissolution rate. Macroemulsions comprise large droplets and thus are unstable in the sense that the droplets sediment or float, depending on the densities of the dispersed phase and dispersion medium. Separation of the dispersed and continuous phases usually occurs within time periods from a few. Surfactants are the principal agents that enable oil and water to mix.
Microemulsions are isotropic, thermodynamically stable transparent or translucent systems of oil, water and surfactant, frequently in combination. Understand the importance of various routes of drug administration to the eye. A generic phase diagram resulting from such analysis is shown in figure 1. Microemulsions show varying rheology depending on the phase point. In wo microemulsions, water droplets are dispersed in the continuous oil phase while ow. In contrast, emulsions require a large input of mechanical energy for their formation. It is different from kinetically stable emulsions which will be break into oil and water over time. Preparing a pharmaceutically acceptable dosage form demands a clear. Micelles, microemulsions, liquid crystals, and the structure. In addition, the almost identical system of water, soap, and longchain carbox ylic acid is decisively relevant to the structure of the stratum corneum lipids. The formation of a surfactant film around droplets facilitates the emulsification process and also tends to minimize the coalescence of droplets.
Microemulsions are isotropic, thermodynamically stable systems composed of oil, water, surfactant s and cosurfactants cos or cosolvents. For hemolytic studies, the propofol microemulsions were diluted with 0. Preparation require intense agitation for their formation. They offer the advantage of spontaneous formation, ease of manufacturing and scaleup, thermodynamic stability, and improved drug solubilization and bioavailability. Fills a void in the literature by presenting the basic concepts of microemulsions, essential to understanding their industrial significance, and comprehensive descriptions of the most useful commerical applications. Bicontinuous microemulsions wherein micro domains of oil and water are inter dispersed within the system. Charts the enormous advances that have occurred in the field over the past decade. Oil and water are immiscible and they separate into two phases when mixed, each saturated with traces of the other component capek, 1999. Chemical method, especially microemulsion flooding, plays an important role in enhanced oil recovery technique due to its ability to reduce interfacial. The aqueous phase may contain salts andor other ingredients, and the oil may actually be a complex mixture of different hydrocarbons and olefins.
Water in oil microemulsions wherein water droplets are dispersed in the continuous oil phase. Microemulsions are prepared by the spontaneous emulsification method phase titration method and can be depicted with the help of phase diagrams. These are a special kind of colloidal dispersion that have attracted a great deal of attention because of their ability to solubilise otherwise insoluble materials. Characterization of microemulsions prepared using isopropyl.
The rapidly increasing number of applications for microemulsions has kept this relatively old topic still at the top point of research themes. Microemulsions are clear, thermodynamically stable, isotropic liquid mixtures of oil, water and surfactant, frequently in combination with a cosurfactant. The altmetric attention score is a quantitative measure of the attention that a research article has received online. In petroleum engineers guide to oil field chemicals and fluids second edition, 2015. Micelles, microemulsions, liquid crystals, and the. Learn more about these metrics article views are the countercompliant sum of full text article downloads since november 2008 both pdf and html across all institutions and individuals. Ppt microemulsions powerpoint presentation free to. Remove this presentation flag as inappropriate i dont like this i like this remember as a favorite. Emulsion in which the particles of the dispersed phase have diameters from approximately 1 to 100. In contrast to ordinary emulsions, microemulsions form upon simple mixing of the components. Microemulsions are potential drug carrier systems for oral, topical, and parenteral administration. When compared with emulsions, which are sensitive and metastable dispersed forms, smedds are physically stable formulations that are easy to manufacture.
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