Controlling the morphology and surface property of magnetic/cisplatin-loaded nanocapsules via W/O/W double emulsion method

Abstract

Here, a well-controlled method to prepare magnetic/cisplatin-loaded nanocapsules with different morphologies has been developed by using a W/O/W double emulsion-solvent evaporation technique. This study focuses on the influences of solvent removal method and existence of stabilizers on the characteristics of nanocapsules in a double emulsion procedure. Biodegradable poly(lactic-co-glycolic acid) [PLGA] nanocapsules were used for encapsulation of cisplatin and magnetic nanoparticles. The effect of preparation conditions on the size, morphology and surface properties of PLGA nanocapsules containing cisplatin and magnetic nanoparticle were investigated too. Solvent removal from the double emulsion was carried out by using two methods; slow evaporation at ambient condition and fast evaporation under reduced pressure. PLGA nanocapsules were prepared in the presence of stabilizers during the first and second emulsification steps and also without any stabilizer. Changing in the morphology and decrease in mean diameter of magnetic nanocapsules were observed when slow evaporation was exploited in comparison with evaporation at reduced pressure. It was found that the loading efficiency of cisplatin was dramatically dependent on the solvent removal method. This step had a significant effect on morphology and size. DLS data showed that the mean diameter of magnetic nanocapsules was ranging between 142 and 384nm with polydispersity index of 0.071–0.111 with zeta potential from −10.5 to−16.5mV. On the other hand, the loading efficiency of cisplatin was related to the preparation conditions and was between 41 and 62% (w/w). The prepared nanocapsules were characterized by SEM and AFM to observe surface topography. These micrographs reveal a spherical shape of magnetic nanocapsules with smooth surface and almost no aggregation was observed. TEM analysis was used to investigate the internal morphology of magnetic/cisplatin-loaded nanocapsules, too.