Fast Synthesis of CU2O Hollow Microspheres and Their Application in DNA Biosensor of Hepatitis B Virus

Well dispersed Cu2O hollow microspheres consisted of Cu2O nanoparticles were quickly synthesized in aqueous solution at room temperature (25 degrees C) with polyvinylpyrrolidone (PVP) as surfactant. The influences of the reaction time, PVP amount and pH value of NaOH solution were studied. The formation mechanism of Cu2O hollow spheres is that, with the modification and steric effect of PVP molecules, Cu2O nanoparticles aggregate to form loose aggregations and then quickly transform to hollow spheres through Ostwald ripening. Formation of loose aggregations is the key to the fast synthesis of hollow spheres at low temperature. The application of Cu2O hollow microspheres in DNA biosensor was also investigated. The hollow Cu2O microspheres greatly enhance the immobilization of the DNA probe on the electrode surface and improve the sensitivity of DNA biosensors.