Polymers and Biopolymers in Pharmaceutical Technology

Department of Pharmaceutical Technology, University of Szeged, Hungary 

Polymers and biopolymers have been used in medicine for centuries. These important materials partly have their own therapeutic effect (active substances), and partly ensure the formulation, stability, and applicability of the dosage form (additives). The discovery of controlled drug delivery systems was a major result of research-development in pharmaceutical technology. In these so-called therapeutic systems, polymers ensuring a predetermined rate of membrane or matrix diffusion are used. Mucoadhesion (adhesion to biological surfaces) and the group of stimuli sensitive (environment sensitive) polymers play an important role in controlling the therapeutic effect. 

Keywords Active substances, additives, biodegradable systems, coated systems, dendrimers, environment sensitive systems, matrix diffusion systems, membrane controlled systems, micro, and nanoparticles, mucoadhesion 

The importance of polymers in pharmaceutical technology is proved by the fact that an independent monograph written by Czetsch-Lindenwald [1] was published as long ago as 1963, summarizing the great choice of pol)maers used in pharmacy. Textbooks and manuals published in the past decades also discuss pol)nners [2-9] and focus considerable attention on polymeric and biopolymeric 

Susheel Kalia and Luc Averous (eds.) Biopxjlymers Biomedical and Environmental Applications, (525-558) Scrivener Publishing LLC 

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Polymers and biopolymers can not only be active substances but also preparation bases (e.g. ointment and suppository bases), stabilizing additives in emulsions and suspensions, fillers, binders, disintegrants, lubricants, and gli-dants in tablet preparation. Coating polymers lead us to a major field of modern pharmaceutical technology, which is controlling the release or dissolution of active substances. 

The primary use of cellulose film has been for wrapping purposes. The past years have witnessed a renewed interest in cellulose research and application sparked mostly by technological interests in renewable raw materials and more environmentally-friendly and sustainable recourses. It has been estimated that the yearly biomass production of cellulose is 1.5 tons, making it an inexhaustible source of raw material for environmentally-friendly and biocompatible products [3]. Cellulose derivatives are used for coatings, laminates, optical films, pharmaceuticals, food, and textiles. Numerous new applications of cellulose take advantage of its biocompatibility and chirality for the immobilization of proteins and antibodies and for the separation of enantiometric molecules, as well as the formation of cellulose composite with synthetic polymers and biopolymers. This chapter basically discussed on the medical applications of cellulose. 

Biopolymers are an essential element in improving human health and quality of life. The wide spectrum of physical, mechanical, and chemical properties provided by polymers has increased the extensive research, development, and applications of polymeric biomaterials. The significance of polymers as biomaterials is reflected in the market of medical polymers, estimated to be approximately 1 billion. Many of these polymers were initially developed as plastics, elastomers, and fibers for nonmedical industrial applications. However, they were later developed as biomedical-specific materials. Currently, with rapid growth in modern biology and interdisciplinary collaborative research, polymeric biomaterials are being widely used in pharmaceutical technology with excellent biocompatibility [33]. 

Natural biocompatible and biodegradable macromolecules, especially plant-derived biopolymers, are more accessible, eco-friendly and cost-effective as compared with synthetic polymers [7-11], Thus, starch, dextran, cellulose, pectins, alginates, agar, gums, chitosan, hyaluronic acid, collagen, and gelatin are viable alternatives to synthetic polymers in pharmaceutical technology [12-16]. 

Further advances in technology offered the solution of surface modification of the metal structure of the DES by chemical or physical adsorption of biopolymers or synthetic polymers that would allow enhanced cell adhesion following placement of the stent. Thus, pharmaceutical polymers may be used not only in the design of the actual stent, but also to coat stent surfaces to augment tissue compatibility. At the present time there are a few DES which are approved by the Food and Drug Authority (FDA) for use in humans. These are further discussed below. 

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