A Proposal for a Novel Surface-Stress Based BioMEMS Sensor Using an Optical Sensing System for Highly Sensitive Diagnoses of Bio-particles

摘要

In this paper, a BioMEMS sensor by using a surface-stress sensing approach, connectedto a highly sensitive optical sensing system, is proposed to diagnose varioustypes of biomolecules. The MEMS transducer is composed of a fixed–fixed beamwith immobilized receptors on the surface which is connected to a Ring Resonator(RR) filter. The interaction between the target biomolecules and the receptorsinduces surface stresses on the beam. This stress results in the beam deformationwhich leads to changes in the coupling coefficient of the RR. Consequently,the transmission spectrum of the RR experiences changes, measured by using anoptical photo-detector. Therefore, by analyzing the response of the photo-detectoroutput, one can detect the number of target biomolecules in the sample and assigna level of contamination, infection or bioparticles, caused by the specific disease.Furthermore, the MEMS functional characteristics and the optical properties of theproposed biosensor are designed and analyzed respectively by using the finite elementmethod (FEM) and the finite difference time domain (FDTD) approach. Theobtained functional characteristics of the proposed device show that the presentoptical BioMEMS sensor can be used for highly sensitive diagnoses of various typesof diseases and their progress level.