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In recent years, the seemingly dissimilar applications of polymers in pharmaceutical, medical and cosmetic areas have drawn closer together, due partly to similar materials requirements and partly to similar chemistry in the end uses. This paper indicates how similar polymers can be used in these diverse fields, and how the basic technology is analogous in each case. Examples include poly(saccharides), poly-(peptides), methacrylate derivatives and poly(silicones).

Chitosan is the N-deacetylated product of chitin {(1→4)-linked 2-acetamido-2-deoxy-β-D-glucan}, which is abundant in nature. (1) No abnormal symptom was observed with several animals when chitosan was orally administered at a dosage of 0.7–0.8 g/kg body weight/day for up to 239 days. (2) Apparent digestibility by rabbits was 28–38% for chitin and 39–79% for chitosan, and that both polymers were digested almost completely by hens and broilers. (3) No abnormal symptom was observed with rabbits when low-molecular-weight (LMW)-chitosan (MW about 3,000) or chitosan oligosaccharides (MW 304 – 1,162) were injected intravenously at a dosage of 4.5 mg/kg body weight/day for 7–11 days. (4) Hypocholesterolemic function was observed with chitosan administered orally but not with LMW-chitosan or oligosaccharides injected intravenously. These data strongly indicate that chitosan is usable as a novel carrier of drugs in the drug delivery system for oral and intravenous administration.

The background, formulation, available forms, and clinical applications of a biomaterial have been presented to amplify the materials broad spectrum of used in oral and maxillofacial surgery. These forms of therapy provide a wider area of practice as well as a greater level of patient satisfaction.

A design for a self regulating insulin delivery system via a chemical approach is proposed based on the competitive binding nature of blood glucose and glycosylated insulin to lectin. The glycosylated insulin bound lectin is encapsulated using biodegradable or nondegradable biomedical polymers. The polymer membranes control glucose influx and insulin efflux while subsequent insulin release depends upon the glucose concentration present, a natural biofeedback.

The surface properties of synthetic polymers are important in many industrially significant processes and applications. Because of the critical importance of polymer surface properties in many major industries and in technology in general, good textbooks and monographs are readily available, including several focusing on biomedical problems (Table 1).

During the last decade tremendous efforts have been made in the development and improvement of medical devices, artificial organs and other life support systems. One of the main problems to be overcome if further progress is to be achieved consists of the need to improve the biocompatibility of materials used for the above-mentioned devices and systems. Much basic research has been carried out to understand the complex interface reactions between living systems and biomedical materials to overcome the “trial and error principle” in the development of new biocompatible materials. This chapter summarises some basic aspects of blood-polymer interaction regarding the theoretical understanding of haemocompatibility.

The present chapter is concerned with the electrochemical characterization of biomedical polymers. Together with such properties as the relative hydrophobicity/hydrophilicity and the chemical composition of the surface, the presence of electrical charges is an important additional feature, determining the suitability of materials for artificial implants, dialysis or perfusion membrane supports, and other medical applications.

During this last decade we have seen not only a large increase in the number of polymers being examined for biomedical uses, but more significantly, a great change in how these materials were characterized. Luckily, we no longer see papers in which, for example, the author simply said, “a plastic was implanted”; and we are seeing less data simply being reported as gross observations only.

The surface characterization of biomedical materials prior to the early 1960’s consisted primarily of relatively qualitative observations as to whether surfaces were hydrophobic or hydrophilic (1). Contact angle techniques were well-known and were widely applied in industry, and general correlations had evolved between blood interactions in glass as opposed to siliconized glass tubes. Vroman was just beginning his studies on protein interactions with surfaces (2). There was considerable interest during this time period on the interaction of cells in culture with solid substrates, and there was some attempt to correlate and quantitate that interaction through contact angle measurements (3).

Of major concern in the development of polymers for medication is the question of the biocompatibility of the polymeric system. We have investigated the biocompatibility of various polymers from the inflammatory response perspective utilizing an in vivo cage system. This cage system permits the quantitive determination of various components of the inflammatory response. Quanitative assays will be presented which can be used to determine the temporal variations in cell function in the inflammatory exudate that interacts with the implanted biomedical polymers or drug-polymer delivery systems. In addition, correlative, comparative, and quantitative information on the release characteristics and cellular response, adhesion and activation, that is the biocompatibility, of polymeric systems also will be presented.

The field of biomedical polymers continues to show steady growth in both the basic research and applications areas. The only limit to the suggested uses of polymers in medicine seems to be a limit in our imagination. Some recent popular articles suggest that nearly all parts of the human body could be replaced by some type of a plastic and/or metal device (1,2). Many major problems remain to be solved before this vision could become fact, however. A large number of recent surveys and books attest to the great interest in this important field of science (3–31). These books but scratch the surface and hundreds of articles are published each year in a variety of journals including such specialized ones as the Journal of Biomedical Materials Research and the Transactions of the American Society of Artificial Internal Organs. Courses in the field of biomedical polymers and biomaterials are now offered at many different universities (32).