Advances in the field of micro/nano-electro-mechanical systems (MEMS and NEMS) now offer unique opportunities in the design of small and ultrasensitive analytical methods. MEMs/NEMs have demonstrated their unique advantages when they are combined with chemistry and biology, including fast, real-time responses. In addition, MEMs and NEMS are small enough to be integrated into other devices. One of the most promising MEMs is microcantilevers, which have been proven to be an outstanding transducer for chemical and biological sensors.

  The chemical specificity can be achieved by selection of appropriate receptors that recognize the target analyte and the recognition event can be converted into a measurable nanomechanical signal. The receptors are categorized as chemical receptors and bioreceptors. So far, the chemical receptors used for nanomechanical sensors include crown ethers, calixarenes, specific functional groups, etc. Bioreceptors include enzyme, antibody, microorganism, cell, etc. Receptor immobilization methods applied to nanomechanical sensors include self-assembled monolayers, layer-by-layer technique, polymer doping approach, and conjugation chemistries.

  In this presentation, the author will summarize the receptors and immobilization approaches reported for nanomechanical sensors and interpret the mechanism and dynamic relationship of recognition induced nanomechanical motions.

  Dr. Hai-Feng Ji received his PhD degree of chemistry from Chinese Academy of Science, China, in 1996. After his graduation, he spent one year as a postdoctoral associate in University of Florida under supervision of Dr. Kirk Schanze, then worked under Dr. Thomas Thundat in Oak Ridge National Laboratory between 1998-2000. In 2000, he joined the faculty in the Institute for Micromanufacturing at Louisiana Tech. He is currently the EnvironMEMS group leader at Louisiana Tech. His research interests focus on MEMS devices, surface modification, and nanoassembly. He is currently a co-author of 55 peer-viewed journal articles and book chapters and is one of the most-active researchers in the microcantilever sensors field.