Microencapsulation pharmaceutical applications

Encapsulation involves the incorporation of active ingredients such as flavors, enzymes, cells or other materials in small capsules. The choice of excipients for encapsulation is very important for the encapsulation efficiency and protein stability within the matrix. Applications of this technique have increased in the food and pharmaceutical industries since the encapsulated materials can be protected from moisture, heat or other extreme conditions. Thus their stability is improved and their viability maintained. Powder formation can lower the water activity of the material, the reactivity and the diffusivity of encapsulated compounds, and the diffusivity of residual water. In the food industry microencapsulation is often associated with the already discussed retention of flavor compounds during drying and storage. In pharmaceutical applications, the purpose of microencapsulation is to control the release and improve the bioavailability of active ingredients. 

N Garti, A Aserin. Pharmaceutical emulsions double emulsions and microemulsions. In S Benita, ed. Microencapsulation-Methods and Industrial Applications. New York Marcel Dekker, 1996, pp 411-534. 

Dingier A. et al.. Solid lipid nanoparticles (SLN/Lipopearls) a pharmaceutical and cosmetic carrier for the application of vitamin E in dermal products, J. Microencapsulation, 16, 751, 1999. 

Modern Pharmaceutics Third Edition, Revised and Expanded, edited by Gilbert S. Banker and Christopher T. Rhodes Microencapsulation Methods and Industrial Applications, edited by Simon Benita... 

Microencapsulation technology has been used from 1930s in packaging flavors and vitamins. Since the first commercial product was introduced for the carbonless copying paper, the technology has advanced to a new level. Various microencapsulation techniques are available nowadays, and the microencapsulated products are widely used in pharmaceutical, biomedical, agricultural, food, consumer products, and cosmetic industries. Representative applications of microparticles in the pharmaceutical and biomedical industries include ... 

With the recent advance of biotechnology and polymer chemistry, the use of microparticle systems will continue to grow for a variety of applications. The objective of this article is to provide a review of the technical aspects of the microencapsulation techniques that have been widely used in the pharmaceutical industry and recent advances of the technology so that the pharmaceutical scientists can take full advantage of the existing assets of this area in developing new microparticle systems. 

Light mineral oil is used in applications similar to those of mineral oil. It is used primarily as an excipient in topical pharmaceutical formulations where its emollient properties are exploited in ointment bases see Table I. It is also used in ophthalmic formulations. Light mineral oil is additionally used in oil-in-water and polyethlylene glycol/gylcerol emulsions as a solvent and lubricant in capsules and tablets as a solvent and penetration enhancer in transdermal preparations and as the oily medium used in the microencapsulation of many drugs. ... 

The advent of biotechnology, bioengineering and pharmaceutical delivery systems has increased the requirements for solubility and stability of macromolecules under a variety of versatile and unique conditions and subsequently the use of non-aqueous solvents. Specihc applications include a) isolation, purification, precipitation and crystallization of biopharmaceuticals, b) processing methods such as spray drying and microencapsulation, and c) formulation of proteins for delivery systems requiring high concentrations and prolonged stability, such as implants and depots. 

Nelson, G., 2002. Application of microencapsulation in textiles. International Journal of Pharmaceutics 242, 55—62. 

The entrapment of various materials such as flavors, living cells, and pharmaceutical compounds within capsules for a wide range of applications is of considerable importance in the pharmacenti-cal, chemical, and food industries, as well as in agriculture, biotechnology, and medicine.As a result microencapsulation has been extensively studied since the early to mid-twentieth century. 

Microencapsulation and encapsulated products have found applications in numerous industries such as agriculture, chemical, pharmaceutical, cosmetic, and food industry over the last century. More recently, applications of these particles in biotechnology and medical processes, including cell encapsulation for artificial implants, production of high cell density cultures and recombinant therapeutic proteins encapsulation as a means for delivery, has opened up a brand new field for this technology. " ... 

Since the first commercial application to carbonless copy paper in the 1950s, microencapsulation with coacervation technology has been successfully applied to many other areas, such as food, pharmaceuticals, cosmetics, biotechnology, and agrochemicals. The capsules provide such functions as controlled release, taste masking, improved heat and oxidative stability, reduced volatility/ flammability/toxicity, separation of reactive incompatibles, improved shelf-life, conversion of liquids to solids, and improved flowability as well as material handling. Among various coacervation processes, complex coacervation is most prevalent. 

Although there are various materials available for encapsulation and so as technologies, the challenges do exist concerning the selection of appropriate microencapsulation technique and encapsulation material. The cost consideration of materials for food applications need to be taken into account unlike the pharmaceutical industry, which can tolerate high costs. The majority of materials used for microencapsulation in the food sector are bio-based materials such as carbohydrate polymers (polysaccharides), proteins, lipids, etc. 

Many miaoencapsulation methods have been developed, for applications in food, pharmaceutical, and cosmetic industries. " Encapsulation of polyphenolics has been extensively studied. The application of microencapsulation to polyphenolics can reach one of several of the following goals ... 

Umer, H., Nigam, H., Tamboh, A. M., and Nainar, M. S.M. (2011) Microencapsulation Ehocess, techniques and applications. International Journal of Research in Pharmaceutical and Biomedical Sciences, 2,474-481. 

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