Generalized Characteristics of Resonant Polymer-Coated Microcantilevers in Viscous Liquid Media

Expressions describing the resonant frequency and quality factor of a dynamically-driven, polymer-coated microcantilever in a viscous liquid medium have been obtained. These generalized formulas are used to describe the effects the operational medium and the coating has on the device sensitivity when used in liquid-phase chemical sensing applications. The derived expressions are shown to reduce to well-known formulas for the case of an uncoated cantilever in an invisicid medium and the case of a coated cantilever in air. The theoretical results are compared to existing chemical sensor data in aqueous and viscous solutions.