Preparation of Chlorotoxin-conjugated Superparamagnetic Nanoparticle and its Magnetic Resonance Imaging In Vitro

Objective: The goal of this study was to prepare and characterize superparamagnetic iron oxide-polyethylene glycol-chlorotoxin(SPIO-PEG-CTX) nanoparticles and validate their magnetic resonance imaging properties in vitro. Materials and Methods: SPIO (superparamagnetic iron oxide) was prepared using the coprecipitation method by dropping a solution of ferric iron (Fe3+) and ferrous iron (Fe2+) in a molar ratio of 2:1 to the alkaline solution (OH-). The SPIO was modified with PEG (polyethylene glycol) and CTX (chlorotoxin) on the surface. The particle size and its distribution were analyzed using a laser particle size analyzer, and the core shape was studied using transmission electron microscopy. 3.0T MRI was performed on the SPIO and SPIO-PEG-CTX solutions. Results: The particle sizes of SPIO and SPIO modified by PEG-silane were between 20 nm and 35 nm with a uniform configuration. In vitro magnetic resonance signals of the SPIO and SPIO-PEG-CTX solution had the same variations. With increasing concentrations of the solutions, the signal intensity increased at T1WI, but decreased at T2WI. Conclusion: SPIO-PEG-CTX nanoparticles were prepared and analyzed using in vitro MRI, which provided the theoretical basis for further study of the nanoparticles for use in the early diagnosis of hepatocellular carcinoma.