Permeable-membrane separating detection of vaporized liquid with nanoparticle-functionalized resonant cantilever for solution-noise suppression

This paper presents a highly sensitive sensing system for real-time detection of volatile analyte in aqueous solution. Different from immersing the sensor into the analyte solution where resonance Q-factor is very low, our resonant microcantilever sensor detects the vaporized liquid by the aid of a permeable membrane separation technique. The resonant sensor under such in-air operation features high Q-factor for fine resolution. With functionalized mesoporous silica nanoparticles (MSNs) modified onto the cantilever sensor, the sensing system experimentally performs high-sensitive and repeated detection to ammonium.