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Ultrasensitive Biosensor from Molybdenite Semiconductor Has Potential for Single Molecule Detection
Move over, graphene. An atomically thin, two-dimensional, ultrasensitive semiconductor material for biosensing developed by researchers at the University of California Santa Barbara (UCSB) promises to push the boundaries of biosensing technology in many fields, from health care to environmental protection to forensic industries. Based on molybdenum disulfide or molybdenite (image), the biosensor material — used commonly as a dry lubricant — surpasses graphene’s already high sensitivity, offers better scalability, and lends itself to high-volume manufacturing. Results of the researchers’ study have been published in the April 22, 2014 issue of ACS Nano., with a correction published in the May 27, 2014 issue of ACS Nano. “This invention has established the foundation for a new generation of ultrasensitive and low-cost biosensors that can eventually allow single-molecule detection — the holy grail of diagnostics and bioengineering research,” said Dr. Samir Mitragotri, co-author and professor of chemical engineering and director of the Center for Bioengineering at UCSB. “Detection and diagnostics are a key area of bioengineering research at UCSB and this study represents an excellent example of UCSB’s multifaceted competencies in this exciting field.” The key, according to UCSB professor of electrical and computer engineering Kaustav Banerjee, who led this research, is molybdenite’s band gap, the characteristic of a material that determines its electrical conductivity. Semiconductor materials have a small but nonzero band gap and can be switched between conductive and insulated states controllably. The larger the band gap, the better the material’s ability to switch states and to insulate leakage current in an insulated state.