Microcantilever Arrays With In-Plane Photonic Readout for Biosensing

摘要

Microcantilever sensors exhibit high sensitivity in both liquid and gaseous environments when operated in static deflection mode, in which adsorption of target molecules by a receptor coating on one side of a microcantilever results in microcantilever deflection due to a change in surface stress (1,2). However, traditional microcantilever transduction techniques have not lent themselves to high sensitivity readout of large-scale arrays of microcantilevers on a single chip (3). We have recently demonstrated a new in-plane photonic transduction method that is scalable to simultaneous readout of hundreds of microcantilevers with a readout sensitivity comparable to the best achievable with the laser reflection method used in atomic force microscopy (AFM) (3-6). Moreover, we have integrated multilayer PDMS microfluidics with microcantilever sensing arrays. Prior to integration, individual microcantilevers are functionalized with inkjet deposition and incubated. After integration, on-chip valves and fluid channels are used to rinse the microcantilevers, followed by introduction of fluids containing a target analyte to assess sensing performance. In this paper we review progress toward biosensing with integrated micofiuidic/microcantilever array structures.