In this project, we aim to establish a wash-free, rapid, and multiplexed
immunoassay and a new signal readout method that can perform bio-marker analysis for clinical diagnostics. The optical force transducer is consist of a bare fiber (without coating and majority of cladding) with nanostring, which is used to attach cells, and a laser source. For visualizing the forces, we utilize evanescent field, which occurs at the interface between core and cladding of the fiber during the total internal reflection. The evanescent field can react with the cells to emit light, whose intensity can be used to determine the force.