Supramolecular linker

Gohy JE, Lohmeijer BGG, Alexeev A, Wang XS, Manners 1, Winnik MA, Schubert US (2004) Cylindrical micelles from the aqueous self-assembly of an amphiphilic poly(ethylene oxide)-b-poly(ferrocenylsilane) (PEO-b-PES) block copolymer with a metallo-supramolecular linker at the block junction. Chem Eur J 20 4315 323... 

AFM studies on the thin ( 50 nm) brush layers demonstrate that the dynamics of supramolecular cross-links contribute to the friction of the soft brush surfaces (Fig. 3.11). When the faster 4a cross-linker is added, both the absolute friction values and the coefficient of friction (COF) drop to 30% of those of the uncross-linked PVP control. When the slower cross-linker 4b is added, however, the absolute friction value and the COF increase dramatically both the COF and the absolute friction values for PVP 4b are more than twice that of PVP alone. The absolute lateral force measured is proportional to the normal force applied this is consistent with the model that the more the tip is pressed into the brush layer the more force it takes to drag it laterally through the brushes. 

The conjugation in the molecular wire may be disrupted or modulated to create systems with different properties. For example, a porphyrin Ceo donor-acceptor system linked with a conjugated binaphthyl unit, has a preference for the atropi-somer where the fullerene unit is closer to the porphyrin system, thus increasing the through space interactions [82]. The charge transfer process on a dyad containing a crown ether in the linker structure can be modulated by complexation/ decomplexation of sodium cations [83] but even more interesting is the construction of supramolecular systems where the donor and acceptor moieties are... 

Liu, Y. Li, L. and Chen, Y. (2002) Molecular Recognition Studies on Supramolecular Systems. Part 38. Inclusion Complexation of Organic Dyes by Organoselenium Bridged Bis-(/f-cyclodextrin)s with a Short linker,/. Incl. Phenom. 42, 151-155. 

More recently the application of the biotin-streptavidin approach has been extensively used by Niemeyer and coworkers in order to construct and manipulate supramolecular assemblies of DNA.266 In the formation of three-dimensional networks of DNA, streptavidin acted predominantly as a bivalent linker defining the spatial arrangement of the DNA fragments (Figure 7.40).267 Interestingly, thermal treatment led to well defined nanocircles within which one streptavidin molecule connecting both ends of the DNA.268,269 Although... 

In the following discussion on the fundamental photophysical properties of supramolecular systems, the simple model dyad A-L-B system is again employed for illustration. This consists of two components, A and B, which may be both molecular, or where one may be an electrode surface. At least one of these units is photoactive, and L is a linker or bridge which permits communication between the A and B components. 

Design of supramolecular rosette tape and linker. From T. C. W. Mak and... 

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