The specific hybridization of p53 gene on bead-quantum dot complex in microfluidic chip.

Recently, nanobiosensors using nanoparticles, such as gold, silver, and quantum dots, have been studied extensively. Among them, fluorescence resonance energy transfer (FRET)-based DNA sensor is prominent device, especially for the medical diagnosis and biomolecular investigations. FRET is a phenomenon of the emitted energy transfer from one fluorescent dye to another dye through a convoluted wavelength for the excitation. PDMS-based microfluidic chips with pillar structure were prepared for the detection of exon 7 of p53 gene by using QD-DNA probe attached to polystyrene micro beads. The specific hybridization was investigated with 4 different target oligonucleotides. Fluorescence quenching was observed only from the target oligonucleotide for exon 7 with proper sequence for the hybridization. The fluorescence intensity from QDs decreased rapidly due to hybridization and FRET between QDs and intercalating dyes.