Reduction of interfacial tension between the internal and external phases Can be used to provide essential nutrients like carbohydrates, fats, and vitamins sterile intravenous emulsions Mechanism of emulsification -Formation of protective barrier around globules of the internal phase Formulate externally used products like lotions, creams, liniments, etc. Protect drugs from oxidation or hydrolysis Enhance palatability of drugs with unpleasant taste or odor or mix with oil soluble dye - similar tests Advantages -Improve bioavailability of lipophilic drugs e.g. phase is colorless, then emulsion is w/o type if scattered globules appear red and cont. if continuous phase appears red, then emulsion is o/w type if negative result, then w/o emulsion type Dye solubility test Identification of Emulsion: if light glows/voltmeter deflects, then o/w emulsion type (water conducts electricity better than oil) pair of electrodes connected to external electric source immersed in emulsion or dilute with oil - similar tests Conductivity test Identification of Emulsion: dilute with water, if stable, emulsion is o/w type, if emulsion breaks, emulsion is w/o type The emulsifier molecule creates a ‘bridge’ that attracts water and non-water molecules and enables them to be held close together and not separate.ĭepending on the emulsifier and the quantities used for each water and oil component, emulsions will contain tiny droplets of one of the liquids spread through the other liquid. For example, proteins dissolve better in water than in oil, and so tend to form oil-in-water emulsions (that is, they promote the dispersion of oil droplets throughout a continuous phase of water).Dilution test Identification of Emulsion: Emulsifiers are molecules that contains two different binding sites: hydrophilic (prefer ‘water’ and binds to water molecules) and hydrophobic(avoids ‘water’ and binds to oil molecules). In this role, the micelle is known as a plasma lipoprotein. The phospholipid emulsifies the fat molecules held inside the micelle. A spherical micelle molecule formed by a ring of phospholipids (green) that allows cholesterol/triglyceride fats (inside yellow zone) to be carried in the blood stream (which is mainly plasma water). Classification, variation, food webs and pyramids.Combustion reactions and impact on climate.Atoms elements compounds and mixtures (interactive).B1.6 Waste materials from plants and animals.RSC Learn Chemistry Classic Chemistry Experiments.RSC Classic Chemistry Experiments (1995).Practical Chemistry (Nuffield Foundation/RSC).3.15 Nuclear magnetic resonance spectroscopy.3.14 Organic synthesis and analysis (A2).2.6 Reactions of ions in aqueous solution.2.4 Properties of Period 3 elements and their oxides.1.11 Electrode potentials and electrochemical cells (Redox A2).
1.10 Equilibrium constant Kc for homogeneous systems (Equilibrium A2).3.6 Organic analysis (AS): analytical techniques.1.7 Oxidation reduction equations (Redox AS).1.6 Chemical equilibria and Le Chatelier’s principle.C3.5 Production of ammonia (an example of a reversible reaction).C3.4 Further analysis and quantitative chemistry.C3.3 Calculating and explaining energy change.C2.5 Exothermic and endothermic reactions.C2.3 Atomic structure, analysis and quantitative chemistry.C1.7 Changes in the Earth and its atmopshere.C1.5 Other useful substances from crude oil.
0 kommentar(er)
