Crosslinks, chemical cleavage

Azari and Feeney (7) suggested that human serum transferrin and chicken ovotransferrin underwent structural changes on chelation of metal ions which stabilized the molecule to denaturation and proteolysis. This later was extended (8) to include stabilization to chemical cleavage or modification. A similar interpretation also was made by Glazer and McKenzie (55) who further suggested that the iron complex might provide two crosslinks between widely separated sections of the peptide chains. 

Fig. 15 Amino acid sequences of artificial extracellular matrix (aECM) proteins. Each protein contains a TV tag, a histidine tag, a cleavage site, and elastin-like domains with lysine residues for crosslinking. The RGD cell-binding domain is found in aECM 1, whereas aECM 3 contains the CS5 cell-binding domain. aECM 2 and aECM 4 are the negative controls with scrambled binding domains for aECM 1 and aECM 3, respectively. Reprinted from [121] with permission from American Chemical Society, copyright 2004...

Figure 6.5 Illustrations of nanoscale spherical assemblies resulting from block copolymer phase separation in solution are shown, along with the chemical compositions that have been employed to generate each of the nanostructures (a) core crosslinked polymer micelles (b) shell crosslinked polymer micelles (SCKs) with glassy cores (c) SCKs with fluid cores (d) SCKs with crystalline cores (e) nanocages, produced from removal of the core of SCKs (f) SCKs with the crosslinked shell shielded from solution by an additional layer of surface-attached linear polymer chains (g) crosslinked vesicles (h) shaved hollow nanospheres produced from cleavage of the internally and externally attached linear polymer chains from the structure of (g)...

An alternative to patterning methods that involve chemical reactions such as bond cleavage, crosslinking or oxidation processes, is the use of a binary SAM with one SAM being highly blocking and the other SAM allowing for metal deposition. 

Different labile crosslinkers have different rates of bond cleavage at different temperatures. The temperature required and the mechanism of bond dissociation depend on the chemical structure of the crosslinker. For example, when the labile crosslinker is a diacrylate ester, hydrolysis of the ester linkage becomes the most likely mechanism of de-crosslinking. Proper selection of crosslinker can give particles with different activation temperature. The product... 

The chemical properties of the platinated DNA, termed M13-12A-Pt(-)-Stu I, were investigated by enzymatic, digestion and gel electrophoresis experiments. Platinum completely inhibits cleavage of the DNA by Stu I, as expected from the earlier restriction enzyme mapping studies. In addition, the cis-[Pt(NH3)2 d(pGpG) ] and cA-[Pt(NH3)2 d(pApG) ] intrastrand crosslinks were... 

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