Calix[8]arene based pH-responsive hydrogelators:useful platform for drug delivery

Delivery drugs with improving safety and stability, controllede rate, slow delivery, targeted delivery is the aim that researcher of this area pursue with very different and attractive methods. Among the others, low molecular weight hydrogelators with stimuli responsive functionalities are considered to be of great interest as drug delivery sistems. Recently we have reported the first example of calix[8]arene polyelectrolyte derivatives as pH-responsive hydrogelators able to form gel phases in basic and acidic conditions. In order to evaluate the utility of these hydrogels as delivery sistems, two different set of hydrogels were prepared. The first one, obtained through basic pH-responsive calix[8]arene hydrogelators, has been studied for the loading and release capacity towards steroid and non steroid anti-inflammatory drugs. Acidic pH-responsive calix[8]arene hydrogelators were instead used to check the improvement of aqueous solubility and stability of curcumin, a natural antioxidant that shows many pharmacological and protective activities, for which many nanoformulations have been proposed in recent years.