Polyrotaxane, fluorescent

Further examples of hybrid pseudorotaxanes containing a linear component incorporating two dialkylammonium centres and a 4,4 -bipyridinium unit associated with an assortment of macrocyclic polyethers have been reported. Both multi-component rotaxanes and polyrotaxanes based on the above tetracationic thread were observed to form. The reversible acid-base-controlled dethreading/rethread-ing of such [n]-rotaxanes has been demonstrated using a combination of NMR, absorption and fluorescence spectroscopies. ... 

Fig. 16 Ethidium bromide displacement assay of the DMAEC-a 18-SS-polyrotaxanes polyplex and the LPEI22k polyplex. The recorded fluorescent intensities (F.I.) were expressed relative to the fluorescence intensity of the DNA-EtBr solution in the absence of polycation, after subtracting the fluorescence of EtBr in the absence of DNA under the same buffer conditions...

Complexation of a PPP 42 having carboxylate substituents (Scheme 17) with cyclo dextrin gives a fluorescent polyrotaxane which shows a PL... 

Scheme 17 Polycarboxjdate used to make fluorescent polyrotaxane...

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