Preparation and physicochemical characterization of a novel paclitaxel-loaded amphiphilic aminocalixarene nanoparticle platform for anticancer chemotherapy

Objectives This paper describes the development and optimization of a nanoparticle delivery platform for the anticancer agent, paclitaxel, using a novel amphiphilic carrier, tetrahexyloxy-tetra-p-aminocalix[4]arene (A4C6). Methods Nanoparticles were successfully prepared at pH 4 by an emulsion evaporation method whereby an organic phase containing paclitaxel : A4C6 (molar ratio 1 : 10) was dispersed by probe sonication into an aqueous phase containing 0.5% w/v polyvinyl alcohol as stabilizer. Key findings The drug-loaded nanoparticles had a mean size of 78.7 +/ 20.7 nm, surface potential of 38.3 +/ 7.67 mV, and paclitaxel loading and encapsulation efficiencies of 69.1 +/ 5.3 mu g drug/mg carrier and 50.4 +/ 3.2%, respectively. Transmission electron micrographs showed discrete particles with no evidence of agglomeration. In-vitro dissolution into phosphate buffered saline supplemented with 4% bovine serum albumin showed 32.7 +/ 3.9%, 82.6 +/ 5.3% and 91.0 +/ 6.0% of the encapsulated paclitaxel load was released at 5, 72 and 120 h, respectively. Conclusions This is the first report on the use of amino-substituted amphiphilic calixarenes for the encapsulation of anticancer agents. The nanoparticles produced were significantly smaller than, but had comparable drug loads to the Abraxane nanoparticles, and have the potential to achieve targeted delivery of paclitaxel to tumour tissues.