UC San Diego

There has been a rising desire for miniaturized sensing platforms for biomedical point-of-care applications. Optical microfiber and nanofibers have drawn great attention in such fields due to their unique light-guiding property and a versatile structure for constructing miniaturized devices. The flexibility and a small footprint of the micro/nano optical fibers allow them to be easily engineered for various sensing platforms with the ultrasensitive modality. One such modality can be achieved through the highly localized optical near-field of a nanofiber with a subwavelength dimension. On the other hand, microfibers with flexible nature yield an adaptable platform that can be easily integrated with other sensing modalities leads to highly localized multifunctional microdevices. In this dissertation, I introduced three fiber optic-based sensing platforms as a compact solution for biomedical applications. We demonstrated ultrasensitive nanomechanical sensing harnessing the sharp decaying optical field outside a nano-fiber optic; a miniaturized multifunctional electro-optic device for neurotransmitter detection; and a microfiber based electrochemical sensor for anticoagulant drug detection. The proposed device architecture, design, engineering solution for device integration of the fiber-based sensing platforms could provide new directions for future research in miniaturized biomedical sensing technologies.