Magnetite loaded Polypeptide-PLGA multifunctional microbubbles for dual-mode US/MR imaging

Abstract

Magnetite loaded Polypeptide-PLGA multifunctional microbubbles (Fe3O4/Polypeptide-PLGA MMBs) that show superparamagnetic properties were prepared by a modified double emulsion method and employed as imaging agent for dual-mode Ultrasound/Magnetic resonance (US/MR) imaging of prostatic cancer. The successful synthesis of MMBs was determined by Fourier Transform Infrared Spectrometer (FTIR), X-ray diffraction (XRD), Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), Atomic Absorption Spectroscopy (AAS) and vibrating sample magnetometer (VSM). The as-prepared MMBs had a diameter of 700 nm and were quite safe as confirmed by MTT assays. Prussian Blue Staining showed that targeted Fe3O4/Polypeptide-PLGA MMBs enhanced the cellular uptake efficiency. In cell attachment study, adherence of MMBs was significantly higher to LNCaP cells compared with negative control PC3 cells. The in vitro results demonstrated that these MMBs could enhance both US and MR imaging of prostatic cancer.