A chemiluminescence biosensor based on the adsorption recognition function between Fe₃O₄@SiO₂@GO polymers and DNA for...

In this work, a chemiluminescence (CL) biosensor was prepared for ultrasensitive determination of deoxyribonucleic acid (DNA) based on the adsorption recognition function between core-shell Fe₃O₄@SiO₂ - graphene oxide (Fe₃O₄@SiO₂@GO) polymers and DNA. The Fe₃O₄@SiO₂@GO polymers were composed by GO and magnetite nanoparticles. And the core-shell polymers were confirmed by Scanning Electron Microscope (SEM), X-Ray Powder Diffraction (XRD) and Fourier Transform Infrared (FTIR). Then Fe₃O₄@SiO₂@GO was modified by DNA. Based on the principle of complementary base, Fe₃O₄@SiO₂@GO-DNA was introduced to the CL system and the selectivity, sensitivity of DNA detection was significantly improved. The adsorption properties of Fe₃O₄@SiO₂@GO to DNA were researched through the adsorption equilibrium, adsorption kinetic and thermodynamics. Under optimized CL conditions, DNA could be assayed with the linear concentration range of 5.0×10^-12-2.5×10^-11mol/L. The detection limit was 1.7×10^-12mol/L (3δ) and the relative standard deviation (RSD) was 3.1%. The biosensor was finally used for the determination of DNA in laboratory samples and recoveries ranged from 99% to 103%. The satisfactory results revealed the potential application of Fe₃O₄@SiO₂@GO-DNA-CL biosensor in the diagnosis and the treatment of human genetic diseases.