Screening unlabeled DNA targets with randomly ordered fiber-optic gene arrays

We have developed a randomly ordered fiber-optic gene array for rapid, para llel detection of unlabeled DNA targets with surface immobilized molecular beacons (MB) that undergo a conformational change accompanied by a fluoresc ence change in the presence of a complementary DNA target. Microarrays are prepared by randomly distributing MB-functionalized 3-mu m diameter microsp heres in an array of wells etched in a 500-mu m diameter optical imaging fi ber. Using several MBs, each designed to recognize a different target, we d emonstrate the selective detection of genomic cystic fibrosis related targe ts. Positional registration and fluorescence response monitoring of the mic rospheres was performed using an optical encoding scheme and an imaging flu orescence microscope system.