Preparation and Characterization of Paclitaxel Loaded SF/PLLA-PEG-PLLA Nanoparticles via Solution-Enhanced Dispersion by Supercritical CO₂

Paclitaxel loaded silk fibroin/PLLA-PEG-PLLA (PTX-SF/PLLA-PEG-PLLA) nanoparticles with a mean particle size of about 651 nm were fabricated successfully by the SEDS process. Fourier transform infrared (FTIR) spectroscopy analysis indicated that the PTX was encapsulated by SF/PLLA-PEG-PLLA nanoparticles. X-ray powder diffraction (XRPD) analysis supported the results of FTIR analysis and also suggested that the crystalline state of PTX was decreased obviously. Furthermore, the UV-Vis/HPLC analysis showed that drug load (DL) and encapsulation efficiency (EE) were 18.1% and 90.2%, respectively. The in vitro drug release experiment suggested that the PTX-SF/PLLA-PEG-PLLA nanoparticles exhibited a sustained release and only 16.1% and 24.5% of paclitaxel were released at pH 7.4 and 6.0, respectively, in one week. The PTX-SF/PLLA-PEG-PLLA nanoparticles drug delivery system with pH-dependent release property has potential application in the field of tumor therapy.