Synthesis and characterization of novel amphiphilic copolymer stearic acid-coupled F127 nanoparticles for nano-technology based drug delivery system

Pluronic, F127, amphiphilic block copolymers, are used for several applications, including drug delivery systems. The critical micelle concentration (CMC) of F127 is about 0.26–0.8 wt% so that the utility of F127 in nano-technology based drug delivery system is limited since the nano-sized micelles could dissociate upon dilution. Herein, stearic acid (SA) was simply coupled to F127 between the carboxyl group of SA and the hydroxyl group of F127, which formed a novel copolymer named as SA-coupled F127, with significantly lower CMC. Above the CMC 6.9 × 10−5 wt%, SA-coupled F127 self-assembled stable nanoparticles with Zeta potential −36 mV. Doxorubicin (DOX)-loaded nanoparticles were made, with drug loading (DL) 5.7 wt% and Zeta potential −36 to −39 mV, and the nanoparticles exhibited distinct shape with the size distribution from 20 to 50 nm. DOX-loaded nanoparticles were relatively stable and exhibited DOX dependant cytotoxicity toward MCF-7 cells in vitro. These results suggest that SA-coupled F127 potentially could be applied as a nano-technology based drug delivery method.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A novel amphiphilic copolymer stearic acid-coupled F127 was synthesized. ► The CMC for SA-coupled F127 was 6.9 × 10−5 wt%, lower about 2 × 103-fold than 0.388 wt% of F127. ► The Zeta potential of nanoparticles formed by SA-coupled F127 was around −36 mV. ► DOX loaded nanoparticles showed potential applications in drug delivery system.