Loading Brucea javanica Oil into pH-sensitive Chitosan Grafted Mesoporous Silica Nanoparticles by Supercritical Carbon dioxide Impregnation

The anti-tumor effect of Brucea javanica oil is remarkable, but the existing preparations have serious deficiencies in targeting and controlled release. This work developed a pH-sensitive Brucea javanica oil mesoporous silica Nano drug delivery system to improve the insufficient controlled release and targeting properties of the preparations. The pH-sensitive mesoporous silica Nano drug delivery system containing Brucea javanica oil was prepared using the supercritical solution impregnation technique. The structure was characterized by scanning electron microscope, Fourier transform infrared, X-ray diffractometer, thermal analysis and nitrogen adsorption-desorption analysis, and the in vitro pH-responsive release behaviour was evaluated. The supercritical solution impregnation method successfully loaded Brucea javanica oil into chitosan-modified mesoporous silica, with an encapsulation rate of over 90 %. Scanning electron microscope, Fourier transform infrared, X-ray diffractometer, thermal analysis and nitrogen adsorption-desorption analysis confirmed the successful preparation of the chitosan-modified mesoporous silica Nano drug delivery system of Brucea javanica oil. In vitro dissolution tests demonstrated that the cumulative release rate of Brucea javanica oil increased significantly as the solution pH dropped from 7.0 to 5.8, at which point the goal of pH-controlled release of Brucea javanica oil was achieved. The supercritical solution impregnation method successfully prepared the pH-sensitive Brucea javanica oil mesoporous silica Nano drug delivery system, which is expected to enhance the controlled release and targeting of Brucea javanica oil preparations..