Supramolecular nanoscale systems based on amphiphilic tetramethylensulfonatocalix[4]resorcinarenes and cationic polyelectrolyte with controlled guest molecule binding

<p>The water-soluble tetramethylensulfonatocalix[4]resorcinarene with methyl (<b>C1</b>) and pentyl (<b>C5</b>) substitutes on the lower rim forms colloid nanoscale aggregates with poly(diallyldimethylammonium chloride) (<b>PDDA</b>) in aqueous solutions. The size and stability of nanoparticles depend on concentrations of the components and their ratio in the ‘calixarene-polymer’ system. Ternary supramolecular complexes «polymer–macrocycle–guest molecule L-tryptophan (<b>Trp</b>) in conditions of spontaneous pH (3.80 and 4.78 for <b>C1-PDDA</b> and <b>C5-PDDA</b> systems, respectively) in an aqueous solution and in phosphate buffer (pH 7) were investigated by fluorescence method. The addition of the third component – <b>PDDA –</b> to the «non-aggregated <b>C1</b>–<b>Trp</b>» associates leads to the release of <b>Trp</b> in all studied conditions. The possibility of the «binding–release» process of L-tryptophan in «<b>C5</b>–<b>Trp</b>» associates after <b>PDDA</b> addition in the ternary complex is achieved and controlled by the structure of the macrocyclic self-associates and pH conditions.</p

Nanoconjugates of a calixresorcinarene derivative with methoxy poly(ethylene glycol) fragments for drug encapsulation

In order to obtain a non-toxic amphiphilic calixresorcinarene capable to form nanoconjugates for drug encapsulation, tetraundecylcalixresorcinarene functionalized by methoxy poly(ethylene glycol) chains has been synthesized. The macrocycle obtained is characterized by low hemotoxicity. In aqueous solution it forms nanoassociates that are able to encapsulate organic substrates of different hydrophobicity, including drugs (doxorubicin, naproxen, ibuprofen, quercetin). The micelles of the macrocycle slowed down the release of the hydrophilic substrates in vitro. In physiological sodium chloride solution and phosphate-buffered saline, the micelles of the macrocycle acquire thermoresponsive properties and exhibit a temperature-controlled release of doxorubicin in vitro. The combination of the low toxicity and the encapsulation properties of the obtained calixresorcinarene–mPEG conjugate shows promising potential for the use as a supramolecular drug-delivery system