Chemical energy self-assembly achieved

In contrast to the top-down approach, a bottom-up approach to tissue fabrication may be achieved by the assembly of repeating subunits in a predictable and directed manner to form larger functional and organized stmctures. In this regard, self-assembly may be defined as the preferential organization and linkage of micrometer-scale stmctures by interactions based upon shape, chemical moieties, or interfacial energy. 

Chemical Energy Achieves De-mixing and Self-assembly... 

Continuing with the mixed solution of Polymers I and XII as defined in Table 6.1, separation and self-assembly can also be achieved with the addition of chemical energy at constant temperature. The addition of a chemical energy, such as the addition of salt at 25° C to a solution of poly(GVGVP) plus poly(GVGIP), just sufficient to lower the temperature of the polymer with the lower transition temperature. Polymer Xn, to below the operating tempera-... 

The similarities in chemical behaviour across the lanthanides mean that kinetically stable lanthanide complexes offer a degree of control that cannot readily be achieved through selective self-assembly of small building blocks. Azamacrocycle complexes derived from cyclen amino-carboxylates are particularly suited to this, and ternary complexes can be used to study the photophysical behaviour of lanthanide complexes. We initially used such an approach to probe the effectiveness of chromophores as sensitizers for lanthanides without recourse to extensive synthesis (as illustrated in Fig. 7). This approach can be used with simple chromophores to probe the mechanism of energy transfer. For instance, tetrathiafulvalene... 

Surface Modification. To achieve a wide surface-energy range, self-assembled monolayers (SAMs) of 11-mercaptoundecanol and dodecanethiol (Aldrich Chemicals, USA) were chemisorbed in both pure and mixed forms on freshly gold-coated samples. The sanples were immersed in 0.1 mM ethanolic thiol solutions for 20 min. For the solution preparation, the total thiol concentration of 0.1 mM was held constant, and the composition of the two compounds was varied in terms of dodecylthiol molar ratio from 100, 70, 50, 45, 30, 15, 10 (GTM only) to 0%. After assembly, the samples were rinsed with ethanol (purity >99.8%, Merck, Germany) and dried under a stream of nitrogen. 

---