DOCSLIB.ORG

Preparation and Characterization of Oil-In-Water and Water-In-Oil Emulsions

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Preparation and Characterization of Oil-In-Water and Water-In-Oil Emulsions 1 Preparation and Characterization of Oil-in-Water and Water-in-Oil Emulsions Prepared For Dr. Reza Foudazi, Ph.D. Chemical and Materials Engineering New Mexico State University By Muchu Zhou May 10, 2016 2 1 Introduction 1.1 Purpose of This Report The objective of this report is to clarify what I have done this semester for research course CHME 498. The research interest is “Preparation and Characterization of Oil-in-Water and Water-in-Oil Emulsions”. Thus, I would like to talk about what is emulsion, what are the main characteristics of emulsions, what are the existing methods for preparations of emulsions and how to make simple emulsions. 1.2 Background of This Report Emulsion is a kind of mixture comprised of two or more liquids, which usually are immiscible, and surfactant. The common types of emulsions are oil-in-water emulsion and water-in-oil emulsion. According to Aronson (1988), the emulsions have important industrial value in the wide range of field and it has been studied extensively recently. The emulsions play an important role in the industrial production and it has been applied to many fields including food industry, cosmetics industry and pharmaceutical industry. In the food industry, emulsifier can function as dough conditioners in order to improve tolerance to variations in flour and other ingredient quality. In the cosmetic industry, the majority of facial creams and lotions are emulsions. 1.3 Scope of This Report 3 This report is going to cover the following contents. Introduction of emulsions. Effect of surfactant. Common materials for preparation of emulsions. Main methods to make emulsions. How to make simple emulsions. Conclusions. 2 Emulsions 2.1 Introduction to emulsions What is emulsion? Emulsion is two or more different immiscible liquids with a surfactant. Thus, there is going to be two phases, one is continuous phase and another one dispersed phase. Generally speaking, the two phases are oil phase and water phase. Generally speaking, there are two common types of emulsions, one is oil-in-water emulsion, and another one is water-in-oil emulsion. The oil-in-water emulsion is usually common. Figure 2-1-1: Introduction to emulsion 4 Mason, T., Wilking, J., Meleson, K., Chang, C., & Graves, S. (2006). Nanoemulsions: Formation, structure, and physical propertites. Figure 2-1-2: The types of emulsion 2.2 Instability of Emulsions According to Aronson (1988), there are two main kinds of instabilities of emulsions, which are flocculation and coalescence. The flocculation is a reversible aggregation of droplets, which could result in phase separation in the field of gravity. Compare with flocculation, coalescence is caused by the rupturing of film of the continuous phase and it is a fusion of droplets into a larger droplets so that there will be separation of emulsion into discrete bulk phases. 5 Figure 2-2-1: Flocculation Figure 2-2-2: Instability of emulsions 2.3 Microemulsion and Nanoemulsion Moreover, there is existing microemulsion and nanoemulsion. Microemulsion is a kind of thermodynamically stable isotropic liquids including oil, water and surfactant. In the most microemulsion phases, the surfactant is highly soluble in both liquid phases. However, the nanoemulsion is a type of traditional emulsion and the droplets size is different. 6 According to Gupta (2010), the composition of the microemulsion and nanoemulsion are similar, are oil, water and surfactant. The droplets size is similar either. And the particle structure is similar, which is small spherical particles consisting of oil and surfactant molecular dispersed in the water phase. Yet they are absolutely different since the nanoemulsion is formed by mechanical shear and the micro emulsion is formed by self-assembly, that is why the microemulsion could be made without and external energy. 3 Effect of Surfactant The surfactant is so significant, because surfactant affects the emulsification in many ways. 3.1 Lowers interfacial tension If two immiscible liquids are in contact with each other, they will tend to maintain as small as interface as possible. Consequently, it is very difficult to mix them. When you shake them, they will become spherical droplets, but after a while, there will be phase separation since the liquids tend to maintain as small a surface area as possible and an interfacial tension will be maintained. However, when a “surface active” ingredient is added, its molecular will tend to be oriented between the two faces with the polar ends in the polar phase and non-polar ends in the non-polar phase, which will lower the cohesive force. 3.2 Allows an interfacial tension gradient dγ/dz to exist The presence of surfactant allows an interfacial tension gradient to exist which 7 implies that the tangential stress and velocity are no longer continuous across the droplet boundary, and the internal circulation in the droplet is impeded or even be prevented. It facilitates droplet deformation, hence breakup. 3.3 Coalescence is slowed down The instability coalescence is slowed down, it enhance the stability. 3.4 Interfacial instability can facilitate emulsification Interfacial instability may be occur, it facilitates the emulsification process. 4 Common materials for preparation of emulsions The common oil phases are the list as below. Density kg/m3 Boiling Viscosity Structure Point C。 mPa·s Silicone Oil 965-980(25C。) >140 100 Refined 920(20C。) 232 68 Sunflower Oil Paraffin Oil 800(25C。) 260 0.001 / Table 4-1: Common Oil Phases The common surfactants are the list as below. 8 Melt Density kg/m3 Structure Point C。 PGPR 90 / / SDS 204-207 1010 F 68 52 / Table 4-2: Common Surfactants 5 Main methods to make emulsions There are many ways to produce emulsions. What I used is injection and stirring. Injection method is that the disperse phase (oil phase) is injected into the continuous phase and then it could be broken into large droplets. And stirring method is that using some equipments to make emulsion mixed homogenously and broke the large droplets into smaller one. 6 How to make simple emulsions What I have done is made some emulsion samples. The main method is combination of injection with stirring. The procedure is the following steps: Weight the surfactant. 9 Add water. Stir the liquid. Add silicone oil slowly using syringe pump. Stir the mixture for mixing homogeneously. Reduce the droplet size by the shear stress. The following figures are the samples. Figure 6-1: Sample with Ф = 0.4 silicone oil and wt% 1.0 SDS 10 Figure 6-2: Sample with Ф = 0.4 silicone oil and wt% 5.0 SDS Figure 6-3: Sample with Ф = 0.4 silicone oil and wt% 10.0 SDS 11 Figure 6-4: Sample with Ф = 0.3 silicone oil and wt% 5.0 Pluronic F68 Figure 6-5: Sample with Ф = 0.4 silicone oil and wt% 5.0 Pluronic F68 12 Figure 6-6: Sample with Ф = 0.3 silicone oil and wt% 5.0 SDS Figure 6-7: Sample with Ф = 0.4 silicone oil and wt% 5.0 SDS 13 7 Conclusions Figure 7-1: Observation through Microscope The figure as above is oil-in-water emulsion I made through microscope. The black line is from ruler which is 1mm length. The sample composition is wt% 5.0 SDS and Ф0.4 silicone oil. According to measurement, the max diameter is about 44 μm, and the min diameter is about 11μm. Thus, we can conclude that the droplet size is larger than we expected. The new question I need to think about is how to make the droplet size become much smaller. Increase the agitation energy means higher rotating speed when mixing two phases. If there is higher mixing speed, more shear stress could be obtained and the shear stress is significant in the disruption of droplets. The objective is to generate smaller stable droplets. We want to have rapid adsorption, lower the interfacial tension and form protective membrane. And we want to control the droplet size, so the disruption of droplet size is significant. 14 8 Appendix Method Related Drop Drops Energy Mode of Restrictionsd to formation manly densityb operationc method disrupted bya 1.Shaking 4a + (T) L B N 2.Pipe flow a.Laminar 5 (+) V L - M C V 4a + T L - M C N b.Turbulent 3.Injection 10a + - L C 4.Stirring a.Simple 1, 2b + T, V L B, C stirrrer b.Rotor- (5) + T, V M - H B, C stator c.Scraper 5 + V L - M B, C V 8a + ? L B, C N d.Viberator 5.Colloid 2a, 4c, 6 (+) V M - H C V mill 6.Ball and 5 + V M B (C) V roller mills 7.High-press. (2b) - T, C, V H C N homogenizer 8.Ultrasonic a.Vibrating 4d + C, T M - H C W knife + C M - H B, C W b.Magneto- striction aV = viscous forces in laminar flow, T = turbulence, C = cavitation. bL = low, M = moderate, and H = high. cB = batch and C = continuous dThe continuous phase should be V = viscous, N = not too viscous, W = aqueous. (This table is from “Encyclopedia of Emulsion Technology, Volume 1”) 9 References Aronson, M. P. (1989). The role of free surfactant in destabilizing oil-in-water 15 emulsions. Langmuir, 5(2), 494-501. Elbers, N. A., Jose, J., Imhof, A., & van Blaaderen, A. (2015). Bulk Scale Synthesis of Monodisperse PDMS Droplets above 3 μm and Their Encapsulation by Elastic Shells. Chemistry of Materials, 27(5), 1709-1719. Fryd, M. M., & Mason, T. G. (2012). Advanced nanoemulsions. Annual review of physical chemistry, 63, 493-518. Gupta, A., Eral, H. B., Hatton, T. A., & Doyle, P. S. (2016).
Load more

Recommended publications
  • An Introduction to Fast Dissolving Oral Thin Film Drug Delivery Systems: a Review
    Muthadi Radhika Reddy /J. Pharm. Sci. & Res. Vol. 12(7), 2020, 925-940 An Introduction to Fast Dissolving Oral Thin Film Drug Delivery Systems: A Review Muthadi Radhika Reddy1* 1School of pharmacy, Gurunanak Institute of Technical Campus, Hyderabad, Telangana, India and Department of Pharmacy, Gandhi Institute of Technology and Management University, Vizag, Andhra Pradesh, India INTRODUCTION 2. Useful in situations where rapid onset of action Fast dissolving drug delivery systems were first developed required such as in motion sickness, allergic attack, in the late 1970s as an alternative to conventional dosage coughing or asthma forms. These systems consist of solid dosage forms that 3. Has wide range of applications in pharmaceuticals, Rx disintegrate and dissolve quickly in the oral cavity without Prescriptions and OTC medications for treating pain, the need of water [1]. Fast dissolving drug delivery cough/cold, gastro-esophageal reflux disease,erectile systems include orally disintegrating tablets (ODTs) and dysfunction, sleep disorders, dietary supplements, etc oral thin films (OTFs). The Centre for Drug Evaluation [4] and Research (CDER) defines ODTs as,“a solid dosage 4. No water is required for the administration and hence form containing medicinal substances which disintegrates suitable during travelling rapidly, usually within a matter of seconds, when placed 5. Some drugs are absorbed from the mouth, pharynx upon the tongue” [2]. USFDA defines OTFs as, “a thin, and esophagus as the saliva passes down into the flexible, non-friable polymeric film strip containing one or stomach, enhancing bioavailability of drugs more dispersed active pharmaceutical ingredients which is 6. May offer improved bioavailability for poorly water intended to be placed on the tongue for rapid soluble drugs by offering large surface area as it disintegration or dissolution in the saliva prior to disintegrates and dissolves rapidly swallowing for delivery into the gastrointestinal tract” [3].
    [Show full text]
  • Int. J. Environ. Res. Public Health
    Int. J. Environ. Res. Public Health 2015, 12, 9988-10008; doi:10.3390/ijerph120809988 OPEN ACCESS International Journal of Environmental Research and Public Health ISSN 1660-4601 www.mdpi.com/journal/ijerph Review E-Cigarettes: A Review of New Trends in Cannabis Use Christian Giroud 1,2,3,*, Mariangela de Cesare 4, Aurélie Berthet 2,3,6, Vincent Varlet 1,2,3, Nicolas Concha-Lozano 2,3,6 and Bernard Favrat 2,3,5,7 1 Forensic Toxicology and Chemistry Unit, University Center of Legal Medicine (CURML), CH-1000 Lausanne 25, Switzerland; E-Mail: [email protected] 2 Department of Community Medicine and Health (DUMSC), Rue du Bugnon 44, CH-1011 Lausanne, Switzerland; E-Mails: [email protected] (A.B.); [email protected] (N.C.-L.); [email protected] (B.F.) 3 Lausanne University Hospital (CHUV), Rue du Bugnon 46, CH-1011, Lausanne, Switzerland 4 Unità di Medicina e Psicologia del Traffico, via Trevano 4, Casella postale 4044, CH-6904 Lugano, Switzerland; E-Mail: [email protected] 5 Unit of Traffic Medicine and Psychology, CURML, CH-1005 Lausanne, Switzerland 6 Institute for Work and Health (IST), Route de la Corniche 2, CH-1066 Epalinges - Lausanne, University of Lausanne and Geneva, Switzerland 7 Center of General Medicine, Department of Ambulatory Care and Community Medicine (PMU), University of Lausanne, Rue du Bugnon 44, CH-1011 Lausanne, Switzerland * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +41(0)-79-556-58-91; Fax: +41(0)-21-314-70-90. Academic Editor: Paul B.
    [Show full text]
  • Grade 6 Science Mechanical Mixtures Suspensions
    Grade 6 Science Week of November 16 – November 20 Heterogeneous Mixtures Mechanical Mixtures Mechanical mixtures have two or more particle types that are not mixed evenly and can be seen as different kinds of matter in the mixture. Obvious examples of mechanical mixtures are chocolate chip cookies, granola and pepperoni pizza. Less obvious examples might be beach sand (various minerals, shells, bacteria, plankton, seaweed and much more) or concrete (sand gravel, cement, water). Mechanical mixtures are all around you all the time. Can you identify any more right now? Suspensions Suspensions are mixtures that have solid or liquid particles scattered around in a liquid or gas. Common examples of suspensions are raw milk, salad dressing, fresh squeezed orange juice and muddy water. If left undisturbed the solids or liquids that are in the suspension may settle out and form layers. You may have seen this layering in salad dressing that you need to shake up before using them. After a rain fall the more dense particles in a mud puddle may settle to the bottom. Milk that is fresh from the cow will naturally separate with the cream rising to the top. Homogenization breaks up the fat molecules of the cream into particles small enough to stay suspended and this stable mixture is now a colloid. We will look at colloids next. Solution, Suspension, and Colloid: https://youtu.be/XEAiLm2zuvc Colloids Colloids: https://youtu.be/MPortFIqgbo Colloids are two phase mixtures. Having two phases means colloids have particles of a solid, liquid or gas dispersed in a continuous phase of another solid, liquid, or gas.
    [Show full text]
  • Minty Mouthwash Launched
    MARKETPLACE 2D LINGUAL Marketplace is provided as a service to readers using text and images from the manufacturer, supplier or distributor and does not imply endorsement by ORTHODONTICS Vital. Normal and prudent research should be exercised before purchase or Non-visible lingual braces have been available use of any product mentioned. for some time but despite the obvious aesthetic advantages for the wearer, ease of use, cost effec- tiveness and patient comfort have all been cited GIVE YOUR SURGERY Three pre-set positions, back and base as drawbacks by dentists and orthodontists. movements are operated by foot control thus A new 2D system by Forestadent has round A MODERN LOOK eliminating a cross infection risk. The seamless edges and smooth surfaces, allowing free- Not everyone wants to purchase a complete upholstery also benefi ts cross infection dom of movement for the tongue – enabling Treatment Centre when sometimes it’s only the control, providing no available hiding places patients to eat and speak without impairment chair that needs replacing. Takara Belmont’s Pro for bacteria, ensuring optimum hygiene. If your almost immediately after the appliance has been II chair can be sold independently of the Cleo chair is starting to date your surgery call Takara inserted. The self ligating brackets feature a ver- treatment centre and has some unique benefi ts. Belmont on 020 7515 0333 or email tical slot for quick and easy archwire insertion. The folding leg rest gives the chair a modern [email protected]. Alternatively, In addition, the 2D bracket, which has a look that is also extremely practical; its com- all products are available to view total thickness of 1.3 mm to 1.65 mm, can be pact size makes surgeries look less cramped and at either of Belmont’s showrooms bonded directly or indirectly and its clips have the design is a lot less intimidating for patients located in London (020 7515 0333) been designed to open and close easily.
    [Show full text]
  • Low-Flow, Minimal-Flow and Metabolic-Flow Anaesthesia Clinical Techniques for Use with Rebreathing Systems ACKNOWLEDGEMENT: AHEAD of HIS TIME Professor Jan A
    Low-flow, minimal-flow and metabolic-flowLow-flow, anaesthesia D-38293-2015 Low-flow, minimal-flow and metabolic-flow anaesthesia Clinical techniques for use with rebreathing systems Christian Hönemann Bert Mierke Drägerwerk KGaA & Co. AG IMPORTANT NOTES Medical expertise is continually undergoing change due to research and clinical experience. The authors of this book intend to ensure that the views, opinions and assumptions in this book, especially those concerning applications and effects, correspond to the current state of knowledge. But this does not relieve the reader from the duty to personally carry the responsibilities for clinical measures. The use of registered names, trademarks, etc. in this publication does not mean that such names are exempt from the applicable protection laws and regulations, even if there are no related specific statements. All rights to this book, especially the rights to reproduce and copy, are reserved by Drägerwerk AG & Co. KGaA. No part of this book may be reproduced or stored mechanically, electronically or photographically without prior written authorization by Drägerwerk AG & Co. KGaA. Fabius®, Primus®, Zeus® and Perseus® are trademarks of Dräger. AUTHORS Christian Hönemann Bert Mierke PhD, MD PhD, MD Vice Medical Director Medical Director Chief physician in the collegiate system of Chief physician of the Clinic for the department of Anaesthesia and Operative Anesthesiology and Intensive Care Intensive Care, St. Marienhospital Vechta St. Elisabeth GmbH, Lindenstraße 3–7, Catholic Clinics Oldenburger Münsterland, 49401 Damme, Germany Marienstraβe 6–8, 49377 Vechta, Germany Low-flow, minimal-flow and metabolic-flow anaesthesia Clinical techniques for use with rebreathing systems ACKNOWLEDGEMENT: AHEAD OF HIS TIME Professor Jan A.
    [Show full text]
  • Novel Liposomes for Targeted Delivery of Drugs and Plasmids
    Brigham Young University BYU ScholarsArchive Theses and Dissertations 2013-11-15 Novel Liposomes for Targeted Delivery of Drugs and Plasmids Marjan Javadi Brigham Young University - Provo Follow this and additional works at: https://scholarsarchive.byu.edu/etd Part of the Chemical Engineering Commons BYU ScholarsArchive Citation Javadi, Marjan, "Novel Liposomes for Targeted Delivery of Drugs and Plasmids" (2013). Theses and Dissertations. 3879. https://scholarsarchive.byu.edu/etd/3879 This Dissertation is brought to you for free and open access by BYU ScholarsArchive. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. Novel Liposomes for Targeted Delivery of Drugs and Plasmids Marjan Javadi A dissertation submitted to the faculty of Brigham Young University in partial fulfillment of the requirements for the degree of Doctor of Philosophy William G. Pitt, Chair Morris D. Argyle Brad C. Bundy Alonzo D. Cook Randy S. Lewis Department of Chemical Engineering Brigham Young University November 2013 Copyright © 2013 Marjan Javadi All Rights Reserved ABSTRACT Novel Liposomes for Targeted Delivery of Drugs and Plasmids Marjan Javadi Department of Chemical Engineering, BYU Doctor of Philosophy People receiving chemotherapy not only suffer from side effects of therapeutics but also must buy expensive drugs. Targeted drug and gene delivery directed to specific tumor-cells is one way to reduce the side effect of drugs and use less amount of therapeutics. In this research, two novel liposomal nanocarriers were developed. This nanocarrier, called an eLiposome, is basically one or more emulsion droplets inside a liposome.
    [Show full text]
  • Emulsion and It's Applications in Food Processing
    Adheeb Usaid A.S et al Int. Journal of Engineering Research and Applications www.ijera.com ISSN : 2248-9622, Vol. 4, Issue 4( Version 1), April 2014, pp.241-248 RESEARCH ARTICLE OPEN ACCESS Emulsion and it’s Applications in Food Processing – A Review Adheeb Usaid A.S1, Premkumar.J2 and T.V.Ranganathan3 1.Bachelor of Engineering, 2.Research Scholar, 3. Professor Department of Food Processing and Engineering School of Biotechnology and Health Sciences, Karunya University, Coimbatore-641114, Tamilnadu, India. ABSTRACT An emulsion is a heterogeneous system consisting of atleast one immiscible liquid dispersed in another in the form of droplets. Emulsions are classified based on the nature of the emulsifier or the structure of the system. The range of droplets size for each type of emulsion is quite arbitrary. Macro emulsions are the most common form of emulsions used in food industries than nano and micro emulsions. There are several methods are possible and a wide range of equipments are available for emulsion formations. These methods include shaking, stirring and injection, and the use of colloid mills, homogenizers and ultrasonics. The unique nature of emulsions with a narrow size distribution of different sized droplets has number of applications in food industries including bakery products, dairy, candy products, meat products and beverages. Still most applications are waiting for commercial exploitation. Key words: Applications, Colloid mills, Emulsions, Homogenizers, Ulrasonics. I. INTRODUCTION The definition of an emulsion has continued function of an emulsifier is to join together oily and to evolve since the 1930s. Becher (1957),developed aqueous phases of an emulsion in a an elaborate definition from several previous authors.
    [Show full text]
  • Drug Vaping Applied to Cannabis: Is “Cannavaping”
    www.nature.com/scientificreports OPEN Drug vaping applied to cannabis: Is “Cannavaping” a therapeutic alternative to marijuana? Received: 26 January 2016 Vincent Varlet1, Nicolas Concha-Lozano2, Aurélie Berthet2, Grégory Plateel2, Accepted: 19 April 2016 Bernard Favrat3,4, Mariangela De Cesare3, Estelle Lauer1, Marc Augsburger1, Published: 26 May 2016 Aurélien Thomas1,5 & Christian Giroud1 Therapeutic cannabis administration is increasingly used in Western countries due to its positive role in several pathologies. Dronabinol or tetrahydrocannabinol (THC) pills, ethanolic cannabis tinctures, oromucosal sprays or table vaporizing devices are available but other cannabinoids forms can be used. Inspired by the illegal practice of dabbing of butane hashish oil (BHO), cannabinoids from cannabis were extracted with butane gas, and the resulting concentrate (BHO) was atomized with specific vaporizing devices. The efficiency of “cannavaping,” defined as the “vaping” of liquid refills for e-cigarettes enriched with cannabinoids, including BHO, was studied as an alternative route of administration for therapeutic cannabinoids. The results showed that illegal cannavaping would be subjected to marginal development due to the poor solubility of BHO in commercial liquid refills (especially those with high glycerin content). This prevents the manufacture of liquid refills with high BHO concentrations adopted by most recreational users of cannabis to feel the psychoactive effects more rapidly and extensively. Conversely, “therapeutic cannavaping” could be an efficient route for cannabinoids administration because less concentrated cannabinoids-enriched liquid refills are required. However, the electronic device marketed for therapeutic cannavaping should be carefully designed to minimize potential overheating and contaminant generation. The creativity of cannabis users leads to new methods of consumption.
    [Show full text]
  • DOWSIL CE-1689 Smoothing Emulsion
    Beauty and Personal Care Consumer Solutions DOWSIL™ CE-1689 Smoothing Emulsion Moisturization and Color Protection for Hair Feel • Softness, suppleness and flexibility • Increased slipperiness • Ease of wet and dry combing Appearance • Color retention to maintain color depth and intensity Efficacy • Intensive conditioning to diminish the feel and appearance of dryness Create Shampoos and Conditioners for resulting in improved dry combing • Easy to formulate Soft, Smooth Hair and a dry sensory feel (slipperiness and • Excellent for conditioning shampoos flexibility). It also provides enhanced Today’s consumers want products that and rinse-off conditioners that revive color protection in a shampoo. DOWSIL™ perform – especially when a product can and restore hair CE-1689 Smoothing Emulsion is excellent provide multiple benefits. Products that for use in conditioning shampoos and create supple, free-flowing hair are in rinse-off conditioners. high demand. Now you can combine the sleek, smooth, moisturized feel that Performance you can see and feel consumers love with the added benefit DOWSIL™ CE-1689 Smoothing Emulsion of color protection. outperformed competitive silicones in providing moisturization in a shampoo. DOWSIL™ CE-1689 Smoothing Emulsion DOWSIL™ CE-1689 Smoothing Emulsion makes it easy to create beauty with impact. also performed well in providing This silicone emulsion is designed to moisturization benefits compared to other provide enhanced moisturized feel, silicones in a rinse-off conditioner. Increased Moisturization for Shampoos – for Soft, Smooth Moisture Benefits for Other Hair Types and Flexible Hair Additionally, on curly, bleached hair and kinky hair, this The moisturizing benefits of a shampoo formulated with emulsion outperformed the commercial benchmark for shine, DOWSIL™ CE-1689 Smoothing Emulsion were compared to slipperiness and combing in a shampoo and rinse-off conditioner.
    [Show full text]
  • Preventing Wall Slip in Rheology Experiments
    Preventing Wall Slip in Rheology Experiments Tianhong Chen 109 Lukens Drive, New Castle DE 19720 Abstract Wall slip is a common problem when testing highly concentrated emulsions or suspensions on a rheometer. It is usually caused by large velocity gradients in a thin region adjacent to the wall. When slip occurs, the measured viscosity can be significantly lower than the actual viscosity of the sample. To overcome this influence, we have introduced a series of roughened surface geometries, such as crosshatched or serrated plates, which significantly improve the contact between the geometry and the sample to reduce slip. A vane shaped geometry, with a grooved inner surface cup, is also considered to be effective in reducing wall slip. Experimental data have shown the influence of wall slip on rheological test results and the improvement when the crosshatched geometries were used. Introduction Wall slip is a common phenomenon in rheology testing. It usually arises from static, hydrodynamic, viscoelastic, chemical, and gravitational forces acting on a dispersed phase immediately adjacent to solid boundaries. The creation of such a low- viscosity boundary at a wall means that flow of the liquid over this boundary is easier because of the lubrication effect – “slip”. Common liquids that show large slip effects are concentrated solutions of high molecular weight polymers, suspensions of large or flocculated particles, and emulsions of large droplet size. Slip always influences the rheological measurement of these kinds of materials, for example, the viscosity measurements, yield stress analysis, oscillation strain/stress sweep testing, etc. Rheologists have characterized the nature of wall slip in rheology analysis [1-5].
    [Show full text]
  • Veterinary-Catalog-2019.Pdf
    Benson Medical Industries Inc. is a Canadian owned and managed company, specializing in the sale and service of veterinary, hospital and dental products since 1974. Benson Medical's head office is located in Markham, Ontario. We also serve our customers from branch offices and sub-distributors located across Canada, as well as designated sales representatives, office support staff and Clinical Product Specialists. Benson Medical provides technical support and maintains a fully equipped service facility with factory trained personnel for both in-shop and field service repair. Benson Medical Industries carries many items to meet your clinic needs. If you do not find what you are looking for, please contact us for assistance. Benson Medical Industries verifies that all items sold meet the strict Canadian electrical safety authority product approval requirements. We have your best interest in mind. 2 “Where service and support is as important as the quality of the equipment.” 3 91805112 VME2 Anaesthetic Machine 91800070 VMS Standard Anaesthetic Machine 91806600 VMR Table Top (0-4 LPM) 91806300 VMR Table Top (0-1 LPM) Vaporizer Not Included Matrx anaesthesia machines are the number one choice among veterinary professionals around the world for inhalation anaesthesia delivery. For over 50 years, each Matrx anaes- thesia machine has been carefully manufactured to provide you with years of safe, simple and controllable inhalation anaesthesia delivery. There are many models to choose from in wall, stand and tabletop configurations, so we’re sure
    [Show full text]
  • Asian Journal of Pharmaceutical Education and Research Oral Thin
    Available online on www.ajper.com Asian Journal of Pharmaceutical Education and Research Vol -4, Issue-2, April-June 2015 ISSN: 2278-7496 REVIEW ARTICLE Oral thin films: an overview KanikaDhote1, Vinod Dhote2, Subhendu Mishra1 1 Ravishankar College of Pharmacy, Bhopal(M.P) 2 Truba Institute of pharmacy, Bhopal (M.P) Article Received on Abstract: 10 March 2015 Oral thin films (OTFs) are the most advanced and promising new approaches for drug delivery as it offers more flexibility and comfort. These enable an ease of administration, as there is no need to drink high amounts of liquids or swallow large solid dosage forms Also it Accepted on improves the efficacy of APIs by dissolving within minute in oral cavity after the contact with less saliva as 22 March 2014 compared to fast dissolving tablets, without chewing and no need of water for administration. OTF offers an alternative to tablets, syrups or suppositories for the treatment of vomiting and nausea, especially for the pediatric population. *Correspondence for The oral thin-film technology is still in the Author: beginning stages and but most popular because it fulfils all the need of patients. In due course, these formulations having APIs will be commercially launched using the oral Kanika Dhote* film technology. These can be prepared using hydrophilic Ravishankar College of polymers that rapidly dissolves on the tongue or buccal cavity, delivering the drug to the systemic circulation via Pharmacy, Bhopal. dissolution when contact with liquid is made. Water-soluble polymers are used as film formers for fast dissolving films. It State: Madhya Pradesh, seems that the value on the whole oral thin film market will Pin No.
    [Show full text]