Synthesis and characterization of magnetic molecularly imprinted polymer nanoparticles for controlled release of letrozole

Synthesis and characterization of magnetic letrozole imprinted polymer nanoparticles is described herein for the first time. Magnetic molecularly imprinted polymers (MMIPs) were synthesized by precipitation polymerization using methacrylic acid (MAA) as functional monomer and trimethylolpropane trimethacrylate (TRIM) as crosslinker in the presence of letrozole as template and MAA-modified magnetite nanoparticles as magnetic component. The nanoparticles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and a vibrating sample magnetometer (VSM). The synthesized MMIP nanoparticles, with particle size of about 100 nm, showed superparamagnetic features with a saturation magnetization of 12.5 emu·g−1 and had thermal stability below 240 °C. The adsorption experiments indicated better template recognition of MMIP than magnetic non-imprinted polymer (MNIP) nanoparticles. Moreover, the release profile of letrozole from MMIP and MNIP revealed the controlled release ability of MMIP nanoparticles for the letrozole anticancer drug. We also found that applying an external alternative magnetic field results in increasing the rate of the drug release.