Modification of Biopolymers

As shown in Fig. 25b, the systematic tuning of emission wavelength was achieved by the combinatorial introduction of substitutents at the two diversity points on the fluorescent core skeleton. In addition to the synthetic versatility and predictability on emission wavelengths, these novel fluorophores were compatible with the modification of biopolymers and successfully applied in the immunofluorescence (see Fig. 25c). 

On the basis of structural resemblance to enzymes, various kinds of macromolecules were developed as artificial enzymes. These macromolecules are classified mainly into two categories modification of biopolymers and totally synthetic functional polymers. 

J. J. Meister, C. T. Li, K. K. Tewari, and S. Simoliunas, Spring National Meeting of the American Chemical Society, April 22-27, 1990 at the Symposium on the Chemical Modification of Biopolymers, Boston, MA. American Chemical Society Abstracts 199, April, 1990, pp 418. 

The rates of adsorption and chain scission are affected by physicochemical properties of the substrate, such as the molecular weight, chemical composition, crystallinity, and surface area, and also by the inherent characteristics of the enzyme which can be measured in terms of its activity, stability, concentration, amino acid composition, and conformation. Moreover, environmental conditions such as pH and temperature also influence the activity of enzymes. The presence of stabilizers, activators, or inhibitors released from the polymer during the degradation process or additives that are leached out may also affect enzyme activity. Chemical modification of biopolymers may also affect the rate of enzymatic resorption since, depending on the degree of chemical modification, it may prevent the enzyme from recognizing the polymeric substrate. The rate of enzymatic resorption is limited by an enzyme saturation point. Beyond this enzyme concentration, no further increase in the rate of resorption is observed even when more enzyme is added. 

Surface Modification of Biopolymers, First Edition. Edited by Vijay Kumar Thakur and Amar Singh Singha. 

FIGURE 4.1 Schematic approach used in the modification of biopolymers (a) blends, (b) chemical linkages, (c) cross-linking, (d) grafting, and (e) biocomposite formation (i, biopolymer matrix ii, biopolymer fillers iii, surface modified inorganic materials). (See insert for color representation of the figure.)... 

EP 1263472 A2. Modification of biopolymers for improved drug delivery. US Provisional Application No. 60/211,508, Patent application, text from W02001060412A2. 2000. 

Electrical surface modification of biopolymers requires surface activation. In the presence of radicals, the two reactive groups —OH and —NH easily lose their protons into the surrounding environment (Fig. 10.4). The resulting radicals, for example, —O and —NH, are able to anchor to ECMs, after which propagation of the ECMs ensues. The intermediate complex of the radical ECMs-biopolymer is called a radical reactivation stage. 

Slepicka P, Trostova S, Kasalkova NS, Kolska Z, Sajdl P, Svorifk V. Surface modification of biopolymers by argon plasma and thermal treatment. Plasma Processes Polym 2012 9 197-206. 

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