Rapid, cost-effective DNA quantification via a visually-detectable aggregation of superparamagnetic silica-magnetite nanoparticles
silica/magnetite, core-shell, superparamagnetic, DNA quantification, polymerase chain reaction (PCR)
DNA and silica-coated magnetic particles entangle and form visible aggregates under chaotropic conditions with a rotating magnetic field, in a manner that enables quantification of DNA by image analysis. As a means of exploring the mechanism of this DNA quantitation assay, nanoscale SiO2-coated Fe3O4 (Fe3O4@SiO2) particles are synthesized via a solvothermal method. Characterization of the particles defines them to be ~200 nm in diameter with a large surface area (141.89 m2/g), possessing superparamagnetic properties and exhibiting high saturation magnetization (38 emu/g). The synthesized Fe3O4@SiO2 nanoparticles are exploited in the DNA quantification assay and, as predicted, the nanoparticles provide better sensitivity than commercial microscale Dynabeads® for quantifying DNA, with a detection limit of 4 kilobase-pair fragments of human DNA. Their utility is proven using nanoparticle DNA quantification to guide efficient polymerase chain reaction (PCR) amplification of short tandem repeat loci for human identification.
Tsinghua University Press
Qian Liu,Jingyi Li,Hongxue Liu,Ibrahim Tora,Matthew S. Ide,Jiwei Lu,Robert J. Davis,David L. Green,James P. Landers, Rapid, cost-effective DNA quantification via a visually-detectable aggregation of superparamagnetic silica-magnetite nanoparticles. NanoRes.2014, 7(5): 755–764