Multifunctional nanocomposite membrane for chemomechanical transducer

We fabricated a novel chemomechanical transducer by using the multilayered nanocomposite membrane composed of layer-by-layer assembled polymers and single-walled carbon nanotubes (SWNTs). The nanomembrane with SWNT layer embedded in it plays multifunctional roles in chemomechanical sensing such as deformable structure under surface stress, electrode for capacitance measurement, and self-heating for biochemical reactions. The thickness of the nanomembrane is 26 nm and it can be suspended over a large square opening with the side dimension of 120 μm. The fabrication is entirely based on the conventional micromachining without any cumbersome processes such as floating and picking up nanomembranes. The nanomembrane transducer integrated with sensor components for capacitive readout and microfluidic channels is utilized to detect anthrax DNA. The nanomembrane transducer is able to selectively detect up to 0.1 μM of target DNA. The assay platform of the nanomembrane transducer offers valuable attributes such as short detection time (a few hundred seconds) and portability. It is demonstrated that the nanomembrane transducer has an applicability to a fast and portable DNA detection platform with self-heating capability for chemical and biological reaction.