Abstract

we have used arrays of micromechanical biosensors to detect carcinoembryonic antigen (CEA), a protein biomarker associated with various cancers such as colorectal, lung, breast, pancreatic, and bladder cancer. The sensing principle is based on the surface stress changes induced by antigen-antibody interaction on the micromechanical membrane (MM) surfaces. MM consists of a membrane suspended by four piezoresistive sensing components. The isotropic surface stress on the membrane results in a uniaxial stress in each sensing component, which efficiently improves the sensitivity. According to the experiments, it was revealed that MMs have surface stress sensitivities in the order of 2 (mJ/m). This matter allows them to detect CEA concentrations as low as 500 pg mL-1 or 3 pM. This indicates the fact that the self-sensing MM approach is beneficial for pathological tests. Copyright © 2014 SCITEPRESS - Science and Technology Publications. All rights reserved.