A pH Sensor Based on a Microcantilever Coated with Intelligent Hydrogel

Abstract Hydrogels that contain different amounts of amino groups were used to modify microcantilevers for the pH measurements. These microcantilevers deflected upon exposure to various pH solutions due to the swelling and shrinking of the hydrogels. The microcantilever deflection, as a function of pH, is nearly linear in a wide pH range. A significant 1000 nm/pH bending response was observed from a Gel‐4 coated microcantilever, which could be used for precise pH measurements. Such hydrogel coated microcantilevers could potentially be used to prepare microcantilever chemical and biological sensors when molecular recognition agents are immobilized into the polymer.