Fiber loop ringdown DNA and bacteria sensors

Herath C., Wang C., Kaya M., Chevalier D.

JOURNAL OF BIOMEDICAL OPTICS, vol.16, no.5, 2011 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 16 Issue: 5
  • Publication Date: 2011
  • Doi Number: 10.1117/1.3572046
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: biosensors, fiber loop ringdown, evanescent field, DNA, bacteria, DOWN SPECTROSCOPY, BIOSENSOR, INDEX
  • Eskisehir Osmangazi University Affiliated: No


We report a new type of refractive index-based biosensor using a fiber loop ringdown evanescent field (FLRD-EF) sensing scheme, in which the sensing signal is a time constant and detection sensitivity is enhanced by the multipass nature of the ringdown technique. Bulk index-based detections of three different single strand DNAs and one type of bacteria are demonstrated for the FLRD-EF sensors that utilize a partially-etched single mode fiber as the sensor head. Stepwise coating of the sensor head with poly-L-lysine and a probe DNA has enabled surface index-based label-free target DNA sensing. We expect an array of FLRD-EF biosensors to be created, which are superior to counterparts in terms of simplicity, low cost, and high sensitivity. (C) 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.3572046]