Macromolecules, biocompatible

Much of tire science of biocompatibility can be reduced to tire principles of how to detennine tire interfacial energies between biopolymer and surface. The biopolymer is considered to be large enough to behave as bulk material witli a surface since (for example) a water cluster containing only 15 molecules and witli a diameter of 0.5 nm already behaves as a bulk liquid [132] it appears tliat most biological macromolecules can be considered to... 

Probably the most promising polymeric drug carrier system involves polysaccharide molecules. These are natural polymers and are often biodegradable to products that are useful to the host or easily eliminated by the host. Dextrans have been the most extensively used polysaccharide for macromolecular prodrug preparations (79). These materials are biocompatible and the in vivo fate is directly related to their molecular weight. Moreover these macromolecules can be easily targetted to the hepatocytes with D-mannose or L-fucose (20). 

The investigation of macromolecules has just begun to unfold its potential in our lives. Polymer modification is a major frontier introducing needed subtle or gross changes that allow biocompatability, enhanced thermal stability, increased solvent stability, etc. to the modified polymer. 

Lutz, J.F., Borner, H.G., and Weichenhan, K. "Combining ATRP and click chemistry a promising platform toward functional biocompatible polymers and polymer bioconjugates". Macromolecules 39(19), 6376-6383 (2006). 

Ray, W. C., and Grinstaff, M. W. 2003. Polycarbonate and poly(carbonate-ester)s synthesized from biocompatible building blocks of glycerol and lactic acid. Macromolecules, 36, 3557-3562. 

Luo, D. Haverstick, K. Belcheva, N. Han, E. Saltzman, W.M. Poly(ethylene glycol)-conjugated PAMAM dendrimer for biocompatible, high-efficiency DNA delivery. Macromolecules 2002, 35, 3456-3462. 

Sodium hyaluronate, or HA, is a biocompatible polysaccharide that is encountered in medicine and the cosmetics industry. Its macroscopic properties are highly sensitive to its hydration level, which is the reason why it has been the object of many studies. When in its dried state, or scarcely hydrated, it is stiff. In this state it may act as a skin-stiffening agent, smoothing wrinkles for instance. When highly hydrated, it acts as a lubricant that is found in synovial fluid. The elucidation of its hydration mechanism has shown us the role of the developing H-bond network in the change of its properties and, at the same time, the power and sensitivity of IR spectrometry to observe water molecules in macromolecules. 

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