Synthetic biological macromolecules

Many complex systems have been spread on liquid interfaces for a variety of reasons. We begin this chapter with a discussion of the behavior of synthetic polymers at the liquid-air interface. Most of these systems are linear macromolecules however, rigid-rod polymers and more complex structures are of interest for potential optoelectronic applications. Biological macromolecules are spread at the liquid-vapor interface to fabricate sensors and other biomedical devices. In addition, the study of proteins at the air-water interface yields important information on enzymatic recognition, and membrane protein behavior. We touch on other biological systems, namely, phospholipids and cholesterol monolayers. These systems are so widely and routinely studied these days that they were also mentioned in some detail in Chapter IV. The closely related matter of bilayers and vesicles is also briefly addressed. 

Ross-Murphy, SB, Physical Gelation of Synthetic and Biological Macromolecules. In Polymer Gels, Fundamentals and Biomedical Applications DeRossi, D Kajiwara, K Osada, Y Yamauchi, A, eds. Plenum Press New York, 1991 21. 

In contrast to biological macromolecules such as proteins, synthetic polymers are, in general, polydisperse. Their molar masses, which show a broad distribution of... 

Hybrid hydrogels are usually referred to as hydrogel systems whose components are at least two distinct classes of molecules, for example, synthetic polymers and biological macromolecules, interconnected either covalently or noncovalently. They have been of particular interest because... 

J. Janca, Microthermal Field-Flow Fractionation Analysis of Synthetic, Natural, and Biological Macromolecules and Particles, HNB Publishing, New York, 2008. 

There are many natural and biological macromolecules that possess anticancer activity. Cytokines, topoisomerase inhibitors, monoclonal antibodies, thymic hormones, cell growth inhibitors, and enzymes have been used [68], They have been recently reviewed [59,69] and their detailed description is beyond the scope of this article. The main problems connected with the administration of such natural macromolecules is their short intravascular half-life, immunogenicity, and sometimes poor solubility. Their modification with synthetic macromolecules can dramatically increase their therapeutic potential as described below. 

In 1996, about 10 years after the introduction of the first recombinant DNA product for human use, the FDA modified and streamlined the approval process for biotechnology products considered to be well characterized. These modifications, in essence, established the direction of how biologic macromolecules are researched and developed today in biotechnology-based and traditional pharmaceutical companies [2]. Well-characterized biotechnology products include (1) synthetic peptides consisting of fewer than 20 amino acids, (2) monoclonal antibodies and derivatives, and (3) recombinant DNA-derived products. Anticipating future developments, the FDA is also prepared to consider DNA plasmid products as well-characterized when the first medicinal in this class is submitted for approval. CBER now approves well-characterized biopharmaceuticals under the BLA process [3]. 

The first examples of the so-called supramolecular catalysis are based on bioinspired molecular recognition, which is an essential attribute of biochemical systems. Structures such as receptors, antibodies, and enzymes can all recognize a feature that is important for their specific functions, often in the presence of species of quite similar structure. The ability to discriminate depends exclusively on the structural properties of these biological macromolecules. Recent progress in bioor-ganic chemistry has shown that many of these functions can be incorporated into smaller, synthetically more accessible structures as model systems [27]. 

D Esposito, Koenig, J. L. Application of Fourier Transform Infrared to Synthetic Polymers and Biological Macromolecules, in Fourier Transform Infrared Spectroscopy,Ferraro, J. R., Basile, L. J. (Eds.) Academic Press, Vol. 1, chapter 2, 1978... 

A large number of macromolecules possess a pronounced amphiphilicity in every repeat unit. Typical examples are synthetic polymers like poly(l-vinylimidazole), poly(JV-isopropylacrylamide), poly(2-ethyl acrylic acid), poly(styrene sulfonate), poly(4-vinylpyridine), methylcellulose, etc. Some of them are shown in Fig. 23. In each repeat unit of such polymers there are hydrophilic (polar) and hydrophobic (nonpolar) atomic groups, which have different affinity to water or other polar solvents. Also, many of the important biopolymers (proteins, polysaccharides, phospholipids) are typical amphiphiles. Moreover, among the synthetic polymers, polyamphiphiles are very close to biological macromolecules in nature and behavior. In principle, they may provide useful analogs of proteins and are important for modeling some fundamental properties and sophisticated functions of biopolymers such as protein folding and enzymatic activity. 

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