title: Electronic detection of microRNA at attomolar level with high specificity.
abstract: Small RNA (19-23 nucleotides) molecules play an important role in gene regulation, embryonic differentiation, hematopoiesis, and a variety of cancers. Here, we present an ultrasensitive, extremely specific, label-free, and rapid electronic detection of microRNAs (miRNAs) using a carbon nanotubes field-effect transistor functionalized with the Carnation Italian ringspot virus p19 protein biosensor. miRNA-122a was chosen as the target, which was first hybridized to a probe molecule. The probe-miRNA duplex was then quantified by measuring the change in resistance of biosensor resulting from its binding to p19, which selects 21-23 bp RNA duplexes in a size-dependent but sequence-independent manner. The biosensor displayed a wide dynamic range up to 10(-14) M and was able to detect as low as 1 aM miRNA in the presence of a million-fold excess of total RNA, paving the way for simple, point-of-care, low-cost early detection of miRNA as a biomarker in diagnosis of many diseases, including cancer.
authors.affiliation: Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, USA.
authors.forename: Pankaj
authors.initials: P
authors.lastname: Ramnani
authors.forename: Yingning
authors.initials: Y
authors.lastname: Gao
authors.forename: Mehmet
authors.initials: M
authors.lastname: Ozsoz
authors.forename: Ashok
authors.initials: A
authors.lastname: Mulchandani
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D055664:Electrochemical Techniques / Q000379:methods*; D035683:MicroRNAs / Q000032:analysis*; D036103:Nanotechnology / Q000379:methods*
chemical_list: D035683:MicroRNAs