Rapid detection of DNA by magnetophoretic assay

Recently, marine environmental pollution has become more and more serious due to oil spills or the collapse of nuclear power plant resulting in a massive release of hazardous materials to the ocean. These harmful radioactive materials are associated with the random mutation of genes leading to deformity of individuals. So far there has been no effective system for monitoring this marine pollution. Therefore, rapid detection of DNA mutations has become increasingly important in a variety of fields including medical diagnostics and food safety. Herein, we report a rapid, sensitive, qualitative and quantitative approach for DNA detection based on the magnetophoretic assay. The Au-magnetic microparticles (MMPs) nanocomplex was used to generate a color signal and uncombined Au NPs contributed an optical signal that could be directly quantified by UV–Vis absorption spectroscopy of the supernatant after the sample was placed in a magnetic field for 2 min. The linear relationship between signal intensity and the target DNA concentrations (0.1 nM–1.0 μM) was investigated and a limit of quantitation of 0.1 nM was achieved using this method.