Pharmaceutical dosage forms emulsions

This chapter describes the basic principles involved in the development of disperse systems. Emphasis is laid on systems that are of particular pharmaceutical interest, namely, suspensions, emulsions, and colloids. Theoretical concepts, preparation techniques, and methods used to characterize and stabilize disperse systems are presented. The term particle is used in its broadest sense, including gases, liquids, solids, molecules, and aggregates. The reader may find it useful to read this chapter in conjuction with Chapters 8, 12, and 14, since they include some of the most important applications of disperse systems as pharmaceutical dosage forms [1]. 

An interface is defined as a boundary between two phases. The solid/liquid and the liquid/liquid interfaces are of primary interest in suspensions and emulsion, respectively. Other types of interfaces such as liquid/gas (foams) or solid/gas interfaces also play a major role in certain pharmaceutical dosage forms, e.g., aerosols. 

TA Wheatley, CR Steuernagel. Latex emulsions for controlled drug delivery. In JW McGinity, ed. Aqueous Polymeric Coatings for Pharmaceutical Dosage Forms,... 

B Idson. Pharmaceutical emulsions. In HA Lieberman, MM Rieger, GS Banker, eds. Pharmaceutical Dosage Forms Disperse Systems, Vol. 1. New York Marcel Dekker, 1988, pp 199-244. 

Idson, B. (1988) Pharmaceutical emulsions, Chap, pharmaceutical Dosage Forms Disperse Systems,... 

Floyd, A.G. Jain, S. Injectable emulsions and suspensions. 36. In Pharmaceutical Dosage Forms Dispersed Systems, 2nd... 

Rosoff, M. Specialised pharmaceutical emulsions. In Pharmaceutical Dosage Forms Disperse Systems, Lieberman,... 

Riaz, M. Weiner, N. Martin, F. Liposomes in theory of 47. emulsion. In Pharmaceutical Dosage Forms Dispersion Systems Lieberman, H.A., Reiger, M.M., Banker, G.S.,... 

Cetyl alcohol is widely used in cosmetics and pharmaceutical formulations such as suppositories, modified-release solid dosage forms, emulsions, lotions, creams, and ointments. 

Sciarra JJ. Aerosol suspensions and emulsions. In Lieberman H, Rieger M, Banker G, eds. Pharmaceutical Dosage Forms Disperse... 

Emulsions - liquid dispersions usually of an oil phase and an aqueous phase - are a traditional pharmaceutical dosage form. Oil-inwater systems have enjoyed a renaissance as vehicles for the delivery of lipid-soluble dmgs (e.g. propofol). Their use as a dosage form necessitates an understanding of the factors governing the formulation and stability of oil-in-water (o/w) and water-in-oil (w/o) emulsions, multiple emulsions (w/o/w or o/w/o) and microemulsions, which occupy a position between swollen micelles and emulsions with very small globule sizes. Photomicrographs of o/w, w/o systems and multiple emulsions are shown in Fig. 7.10. It is also possible to formulate nonaqueous or anhydrous emulsions, that is oil-in-oil systems and even multiple oil-in-oil-in-oil systems. 

JB Boyett. CW Davis. Injectable emulsions and suspensions. In Liebermann H. A., Rieger M. M., Banker G. S. eds. Pharmaceutical dosage forms. Disperse systems, Vol 2. New York Marcel Dekker, 1989, pp, 397-413. 

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