A new ion-exchange adsorbent with paramagnetic properties for the separation of genomic DNA

Abstract

A new ion-exchange adsorbent (IEA) derived from Fe₃O₄/SiO₂-GPTMS-DEAE with paramagnetic properties was prepared. Fe₃O₄ nanoparticles were firstly prepared in water-in-oil microemulsion. The magnetic Fe₃O₄ particles were modified in situ by hydrolysis and condensation reactions with tetraethoxysilane (TEOS) to form the core–shell Fe₃O₄/SiO₂. The modified particles were further treated by 3-glycidoxypropyltrimethoxysilane (GPTMS) to form Fe₃O₄/SiO₂-GPTMS nanoparticles. Fe₃O₄/SiO₂-GPTMS-DEAE nanoparticles (IEA) were finally obtained through the condensation reaction between the Cl of diethylaminoethyl chloride-HCl (DEAE) and the epoxy groups of GPTMS in the Fe₃O₄/SiO₂-GPTMS. The obtained IEA has features of paramagnetic and ion exchange properties because of the Fe₃O₄ nanoparticles and protonated organic amine in the sample. The intermediates and final product obtained in the synthesis process were characterized. The separation result of genomic DNA from blood indicated that Fe₃O₄/SiO₂-GPTMS-DEAE nanoparticles have outstanding advantages in operation, selectivity, and capacity.