LPGs for biomedical application.pdf

Gratings (LPGs) sensors are tiny periodic in-fiber structure inscribed along the optical fiber. It formed by longitudinal periodic refractive index and/or structural modulation along an optical fiber, which induces resonant coupling between the fundamental mode and co-propagating cladding modes. As higher order modes are strongly attenuated, a series of resonant dips can be observed in the transmissionspectrum. Dependent on fabrication parameters and the hosting fibers resonant wavelengths can be sensitive to the temperature, strain, bending, pressure, curvature et cetera. LPG executes an evanescent wave, which makes a best candidate for the chemical sensors or biosensors. Bare LPGs already used to monitor the respiratory volumes whereas a LPGs coated with different analytes like zinc oxide, gold, silver, TiO2 has been demonstrated for the recognition of bacteria, a platform for DNA/Aptamerdetection, cancer tissue detections and other biomedical applications. Recently Partridge et al. reported that LPGs coated with hemoglobin can be applicable for dissolved oxygen sensing.These LPG fabricated for biomedical applications