HIGH EFFICIENT SEPARATION FOR NUCLEIC ACIDS AND PROTEINS WITH FUNCTIONALIZED SILICA-COATED MAGNETIC NANOPARTICLES

摘要

A method for preparing silica-coated magnetic nanoparticles is provided to produce the magnetic nanoparticles which are capable of separating nucleic acids and proteins selectively and have an amino group, or both an alkyl group and an amino group. A method for preparing silica-coated magnetic nanoparticles having an amino substituent includes the steps of: dispersing magnetic nanoparticles; adding polyvinylpyrrolidone into the dispersed magnetic nanoparticles to stir the admixture, adding an aqueous acetone solution thereto to centrifuge the admixture, and washing the resultant with an organic solvent; adding 10-50mM of tetraethyl orthosilicate thereto, adding a base thereto to maintain pH 11 with stirring, refluxing the resultant at 100-120°C for 20-24hours, and drying the resultant to prepare silica-coated magnetic nanoparticles; dispersing the silica-coated magnetic nanoparticles in an organic solvent, thereto adding at least one compound selected from the group consisting of 3-aminopropyltriethoxysilane, N-[3-(trimethoxysilyl)propyl]ethylene diamine, and N'-[3-(trimethoxysilyl)propyl]diethylene triamine, heating the admixture to 130°C, and refluxing and reacting the admixture for 6-8hours by rapid stirring; and washing and drying the resultant to obtain a product.