Fast and selective recognizes polysaccharide by surface molecularly imprinted film coated onto aldehyde-modified magnetic nanoparticles.

In this work, a starch imprinted magnetic nanoparticles composite material has been successfully synthesized. This molecular imprinted material has promising practical utility in capturing polysaccharides for pharmacology applications. First, we synthesized Fe3O4 nanoparticles by coprecipitation, followed by the modification of tetraethyl orthosilicate (TEOS) and functional amino group and aldehyde group, respectively. Then we used functionalized Fe3O4@SiO2 as the magnetic cores, starch as the template, 3-aminophenylboronic acid (APBA) as the functional monomer and ammonium persulphate (APS) as the initiator. Magnetic molecularly imprinted nanoparticles (MMIPs) were synthesized by surface-imprinted polymerization under airtight tubes at room temperature for 24 h. MMIPs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) analysis. This showed a high saturation magnetization value (5.59 emu g(-1)) easily reached under an external magnetic field. The binding experiments were shown to have relatively high adsorption capacity (15.45 mg g(-1)) and selective recognition ability over structurally related compounds. Therefore, MMIPs provide a sensitive and selective approach and offer the potential to become a new key for polysaccharide separation and purification.