Synthesis of Functionalized Magnetite Nanoparticles

7 Nanoparticle Synthesis and Immobilization Procedures 2.7.1 Synthesis of Functionalized Magnetite Nanoparticles 

Magnetite stock solution (100 mL) was sonicated for 30 min and diluted with ethanol (300 mL) in a two-necked flask equipped with a reflux condenser and a pressure equalized dropping funnel. 3-aminopropyltrimethoxysilane (APTS, 20 mL) was added over 7 h at 60 °C and the nanoparticles were subsequently washed with methanol (3 x 50 mL) by magnetic separation and dried in vacuo. 

16 g of APTS modified magnetite nanoparticles were dispersed in methanol (100 mL) and methyl acrylate (40 mL) was added. After sonication for 5 min the mixture was stirred overnight at room temperature and washed with methanol (5 X 20 mL). Ethylenediamine (8 mL) and methanol (10 mL) were added and stirred at 50 °C for 5 h. This step was repeated twice with increased amounts of methyl acrylate (60 and 80 mL) and ethylenediamine (12 and 20 mL) and the final product was washed with methanol (3 x 50 mL) and water (3 x 50 mL). 

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