title: Low-concentration mechanical biosensor based on a photonic crystal nanowire array.
abstract: The challenge for new biosensors is to achieve detection of biomolecules at low concentrations, which is useful for early-stage disease detection. Nanomechanical biosensors are promising in medical diagnostic applications. For nanomechanical biosensing at low concentrations, a sufficient resonator device surface area is necessary for molecules to bind to. Here we present a low-concentration (500 aM sensitivity) DNA sensor, which uses a novel nanomechanical resonator with ordered vertical nanowire arrays on top of a Si/SiO(2) bilayer thin membrane. The high sensitivity is achieved by the strongly enhanced total surface area-to-volume ratio of the resonator (10(8) m(-1)) and the state-of-the-art mass-per-area resolution (1.8×10(-12) kg m(-2)). Moreover, the nanowire array forms a photonic crystal that shows strong light trapping and absorption over broad-band optical wavelengths, enabling high-efficiency broad-band opto-thermo-mechanical remote device actuation and biosensing on a chip. This method represents a mass-based platform technology that can sense molecules at low concentrations.
authors.affiliation: School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14853, USA. yl676@cornell.edu
authors.forename: Yuerui
authors.initials: Y
authors.lastname: Lu
authors.forename: Songming
authors.initials: S
authors.lastname: Peng
authors.forename: Dan
authors.initials: D
authors.lastname: Luo
authors.forename: Amit
authors.initials: A
authors.lastname: Lal
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D003460:Crystallization; D004247:DNA / Q000032:analysis*; D015342:DNA Probes / Q000737:chemistry*; D004867:Equipment Design; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods*; D053770:Nanowires / Q000737:chemistry; D055096:Optical Devices; D010777:Photochemistry; D017785:Photons; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry
chemical_list: D015342:DNA Probes; D012822:Silicon Dioxide; D004247:DNA