title: Current rectification with poly-l-lysine-coated quartz nanopipettes.
abstract: Ion current rectification with quartz nanopipette electrodes was investigated through the control of the surface charge. The presence and absence of a positively charged poly-l-lysine (PLL) coating resulted in the rectified current with opposite polarity. The results agreed with the theories developed for current-rectifying conical nanopores, suggesting the similar underlying mechanism among asymmetric nanostructure in general. This surface condition dependence can be used as the fundamental principle of multi-purpose real-time in vivo biosensors.
authors.affiliation: Stanford Genome Technology Center, Department of Biochemistry, Stanford University School of Medicine, Stanford University, 855 California Avenue, Palo Alto, California 94304, USA.
authors.forename: Senkei
authors.initials: S
authors.lastname: Umehara
authors.forename: Nader
authors.initials: N
authors.lastname: Pourmand
authors.forename: Chris D
authors.initials: CD
authors.lastname: Webb
authors.forename: Ronald W
authors.initials: RW
authors.lastname: Davis
authors.forename: Kenji
authors.initials: K
authors.lastname: Yasuda
authors.forename: Miloslav
authors.initials: M
authors.lastname: Karhanek
mesh_terms: D004553:Electric Conductivity; D004566:Electrodes; D008422:Materials Testing; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods; D043942:Nanotubes / Q000737:chemistry*; D010316:Particle Size; D011107:Polylysine / Q000737:chemistry*; D011791:Quartz / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013499:Surface Properties
chemical_list: D011791:Quartz; D011107:Polylysine