Pluronic/polyethylenimine shell crosslinked nanocapsules with embedded magnetite nanocrystals (PPMCs) were developed for magnetically triggered delivery of siRNA. The positively charged PPMCs formed stable nanosized polyelectrolyte complexes via electrostatic interactions with negatively charged siRNA‐polyethylene glycol conjugate (siRNA‐s‐s‐PEG) that was linked via a cleavable disulfide linkage. PPMC/siRNA‐s‐s‐PEG polyelectrolyte complexes were efficiently taken up by cancer cells upon exposure to a magnet, thereby enhancing intracellular uptake and silencing effect of siRNA. The present study suggests that these novel nanomaterials could be potentially utilized for magnetically triggered delivery of various nucleic acid‐based therapeutic agents.
A novel thermosensitive polyester with pendant ketoprofen was synthesized by copolymerization of PEG 800 with 2‐ketoprofendimethylmalate using CAL‐B at 70 °C. The products were characterized by NMR spectra and GPC. The in vitro study demonstrated that the polyester could release ketoprofen in physiological conditions, which indicates that the polyester could be a promising prodrug.
