From Synthesis to Application: Functionalized Magnetic Nanoparticles as a Simple and Reliable Tool for Nucleic Acid Purification

High Resolution Image Download MS PowerPoint Slide Magnetic nanoparticles (MNPs) are widely used for nucleic acid (NA) extraction, but their performance strongly depends on the synthesis and surface functionalization. In this work, we applied a design of experiments (DoE) approach to optimize the coprecipitation synthesis of iron oxide nanoparticles, identifying NH 4 OH flow rate and reaction temperature as the key factors. Under optimal conditions (5.5 mL min –1, 65 °C), Fe 3 O 4 nanoparticles were coated with SiO 2 and subsequently functionalized with (3-aminopropyl)triethoxysilane (Fe 3 O 4 @SiO 2 -APTES). The resulting nanoparticles (∼12 nm) were stable and magnetically responsive and provided efficient NA binding. Their performance in NA extraction was validated by RT-qPCR, yielding Ct values (20–25 for S, ORF, and N genes) comparable to those of both silica column and commercial magnetic bead methods. These results demonstrate that DoE is an effective strategy for tailoring nanoparticle synthesis and highlight Fe 3 O 4 @SiO 2 -APTES as a simple, cost-effective, and reliable material for nucleic acid purification in routine laboratory applications.