DNA OPTICAL SENSOR - A RAPID METHOD FOR THE DETECTION OF DNA HYBRIDIZATION

A DNA optical sensor system is proposed based on the combination of sa ndwich solution hybridization, magnetic bead capture, flow injection a nd chemiluminescence for rapid detection of DNA hybridization. Bacteri al alkaline phosphatase (phoA) gene and Hepatitis B virus (HBV) DNA we re used as target DNA. A biotinylated DNA probe was used to capture th e target gene onto the streptavidin-coated magnetic beads and a calf i ntestine alkaline phosphatase (CAP)-labelled DNA probe was used for su bsequent enzymatic chemiluminescence detection. The detection cycle wa s less than 30 min, excluding the DNA hybridization time, which was ab out 100 min. Both the phoA gene and HBV DNA could be detected at picog ramme or femtomole level. No response signal was obtained when target DNA did not exist in the sample. Successive sample detection could be made by removing the magnetic field and a washing step. (C) 1998 Elsev ier Science S.A. All rights reserved.