Cavitand based receptors for sensing and polymers

The present thesis deals with the application of molecular recognition in materials science. In particular, we report the formation of supramolecular polymers and sensor harnessing the outstanding recognition properties of tetraphosphonate cavitands towards N-methylpyridinium and N-methylammonium salts. The first part reports the self-assembly of a stimuli responsive supramolecular homopolymer, obtained by synthesizing a sarcosine derived cavitand monomer. The self-assembly and stimuli responsive properties of the homopolymer have been demonstrated with several techniques (NMR spectroscopy, light scattering, TEM). This host-guest counterpart were embedded in real polymers (PS and PBMA) as comonomers, to test their ability to promote polymer blending, and to investigate the responsiveness of this complex in a truly polymeric material. The second topic concerns the selective sensing of illicit drugs like methamphetamines and cocaine without interference from other molecules bearing N-methylated groups like sarcosine. To this purpose a new fluorescent tetraphosphonate cavitand chemosensor bearing two distal pyrene unit has been designed, synthesized and tested. The fluorescence results indicated that the cavitand is an efficient chemosensor for the family of illicit drugs in aqueous solution. In the final topic we studied the self-assembly of differently charged supramolecular vesicles driven of a ternary host-guest complex based on cucurbit[8]uril. The vesicles size distribution and morphology have been characterized in details by DLS, TEM and ESEM.